An important reminder from Unbalanced Reaction about data backup brought the following question to mind:
How many different types of storage media do you have at home? (I don't care if you have the hardware to read them or not.)
Although I suspect I am missing something, here is my list of the 9 (possibly 11) different types of media that are in my house:
Time to do some more summer house cleaning ....
This is the third of three articles concerning calculators and mathematics triggered by a blogspot and IHE blog article by Dean Dad, a community college dean who appears to be writing from another part of the country yet has the same problems we have at our CC. The original article concerned calculator use in Developmental math classes that typically cover fractions and 7th grade algebra, but the comments spanned a range from that topic through mathematics and its applications beyond calculus. My first article merely laid out a common set of definitions, but does include a few assertions about various types of calculators and levels of mathematics that might deserve comment. The second article tried to focus on Developmental math but also included some comments about Algebra. In between these, I posted a shorter article that included a more polemical set of comments about the "modern" Z80-based Graphing calculators. Comments on the second article made me realize I also owe the community a long-deferred article about the math preparation of elementary ed teachers.
My second article limited itself to classes that are remedial in the sense that their goal is to get students to finally learn skills that were supposed to be taught in elementary and middle school as well as the first year or so of high school. College Algebra occupies a fuzzy territory because it is sometimes learned in high school (where it would be Algebra II) but is considered a college-level math class that is sometimes a general education requirement. I included it in my previous article because it is not the only gen-ed math option at our CC and serves many masters. In this article, I will take up the issue of most interest to me: whether students are prepared to use calculators and algebra to do physics, calculus, and (perhaps) engineering problems.
My expectations
As noted earlier, I allow my students to use a Scientific calculator and I expect them to have a decent one and be fairly fluent in its use. I do not allow them to use a Graphing calculator or one that is capable of doing computer algebra. The former is excluded because I do not have time to police all of them for cheat sheets, the latter is excluded because I want a level playing field. They can use MathCAD or Maple or Mathematica when they get into upper division classes where everyone will be using equivalent tools on any given assignment. I expect them to do algebra with pencil and paper in a freshman physics class.
The calculus teachers here have a similar expectation. Many (but not all) give exams where no calculators are allowed on part of the test, but a Graphing calculator (mainly for the numerical integration feature that is on some Scientific calculators as well) is allowed on others. Sometimes they even use a computer algebra program on an exam, but that is rare.
One thing I mentioned in a comment on Dean Dad's blog was the importance of defining outcomes. I forgot to mention that outcomes are best defined so the match the desired inputs for a subsequent class. It is for that reason that our calculus faculty require that students actually know certain derivatives cold, like times tables, and why they were stunned into disbelief when a student transferred here from a school where they used an Algebraic calculator that can do all of the basic derivatives and integrals symbolically. That outcome (being able to take a derivative with a calculator) is mismatched to the requirements of physics and engineering. (True, an engineer taking the "fundamentals" exam has a reference book handy that contains the basic derivatives, but the few minutes you are given to answer each question does not give you enough time to look up every basic result.)
Physics
In general terms, my views on calculators are similar to what Chad Orzel wrote in response to Dean Dad's blog. Real math (meaning math major math classes) have no need at all for calculators unless the topic is numerical analysis, and then you are better off with a programmable computer. Ditto for upper division physics majors classes, although they can have a computational component as well (that is, arithmetic rather than the symbolic mathematics of algebra or calculus). My impression from former students is that engineering expects correct computation as well as algebra, so exams require computation as well as the proper setup of the problem.
I should add that the exam security issues inherent in larger classes, where students are unavoidably sitting within copying range, also requires numerical variations between problems. (Exam fairness has, so far, kept me from putting totally different problems on versions used in the same class.) Most on-line homework systems also do this, although some have symbolic variations as well as numerical ones. This leads to an emphasis on problems with numerical values.
Further, because my students tell me what they do in their first engineering classes, I know computation is only part of it. Setting up the problem algebraically and simplifying before computing is ALSO part of it. For this reason, I require them to state the problem symbolically before plugging in the numbers. However, primarily because of their comfort level, I do not take off if they do the algebra with numbers present rather than keep the symbols until the end. (Having numbers and unknowns makes it easier for most of them to keep track of what is unknown and needs to be isolated or eliminated.) I'll let someone else break them of that habit later on, but I will encourage them to work on it in my class. That said, I do sometimes give exam problems where a symbol like L has to be in the final answer. See below.
Computing
What has surprised me is the degree to which students either cannot compute efficiently or use their calculators inappropriately when solving a problem.
The first problem has only become evident to me recently. I don't think it is a new development; I just happened to see a particularly egregious case last year where the student would evaluate something like A*B*C/D by doing A*B, write down the answer, enter the answer*C, write down that answer, then enter that answer/D. Painful. And slow. And prone to error. I should have suspected this sort of problem because the other version, entering ((A*B)*C)/(D), is a bit of craziness not uncommon in Algebra classes. They don't know order of operations and, even if they do, some have used bad calculators that violate those rules and been burned.
This is, however, a real handicap. They need to use one calculator type and use it enough to understand what it does under different circumstances, but might never have been taught that it is OK (and even necessary) to hit lots of buttons and see what they do under different circumstances. I'm going to mention that this year, going beyond such simple things as whether your calculator does -3^2 correctly or whether it knows automatically that the arcsin of 2 (or the ln of -1) is imaginary.
The second problem is doing algebra with long messy numbers in the equations. This came up in an earlier blog post about algebra, with some nice observations in the comments. This summer I've been thinking about where this comes from, and I am convinced it is because they never use realistic numbers in Algebra classes. Their equations all have numerical coefficients that are small whole numbers, not the 10 digit value for the y component of the velocity, v*sin(theta). There is no penalty for using 3 as a coefficient. There is a penalty for using 34.5619288 as a coefficient. They also seem to have not been exposed much to subscripts, so they are initially quite uncomfortable using Vx as a symbolic replacement for that nasty number.
My preferred solution would be to have pre-calc and trig classes use symbols with subscripts so they get comfortable with that math skill, just as I would like them to work with functions like g(y) or x(t) or even x(y). As we talk more about outcomes at my college, I have to see where those skills fit into the goals of our math curriculum. It might be that these are one-and-done skills (like some skills in physics) because instructors at one level don't know how important it is when you do kinematics in physics or power series in calculus and how much students struggle with those concepts. However, I also know that this is overly optimistic. Instead, I am thinking about ways to work those in from the beginning in my class, perhaps by starting with y(t) motion rather than x(t) motion and using vy and ay even when they aren't really required at that point.
Finally, there is the way I model doing problems in class. Comment number 4 on Chad's article mentioned math exams where you could only use a calculator on part two, something some of our math teachers do, but then came up with a nice insight: it also could be used to introduce the concept of only taking out your calculator when you reach the stage where you've gotten the problem to its simplest state, and need only put in the numbers.
I've seen students do exactly that while taking an exam, just as I do, but I've never thought about really making a SHOW of pulling out the calculator at that point of the problem. I need to model that step as clearly and explicitly as I model algebraic steps when solving a problem. I also need to find or invent more problems where a symbol is in the final answer, like it would be if you were writing a program where a few values are fed in by the user but others are fixed by material properties or whatever.
One of these years I need to plan that vacation trip that includes a stop at Pearl Harbor before heading on to Japan in early August. I need to see where my car was built and visit ground zero of the first A-bomb used in combat as well as the place where it all started for the US in the Pacific. And Kyoto.
One of the odd things about these anniversaries is that, for my students, much more time has elapsed since Vietnam ended than had elapsed between the end of WW II and when I was finishing high school.
Another odd thing is that the film of the bomb going off was either taken or witnessed by someone I once knew, but he never talked about the experience. (In contrast, other people I know who worked on the Manhattan project or other war-related enterprises - such as code breaking - have shared that history and their views of the project.)
One particular irony is that there was an editorial about radiation exposure limits just a few days ago. (Hat tip to Chad at Uncertain Principles.) The dose limits were adjusted based on what was learned from single (acute) dose exposures at Hiroshima, but the editorial argues that we need to look more closely at the evidence from low level (chronic) exposures documented in the 60+ years since those first studies.
PS - I tweaked the posting time to match when (by Japan time) the bomb was dropped.
I howled when I saw this on xkcd, which I read regularly:
Nailed it!
I visit college web sites while advising future transfer students, and it is rare to find one that makes it easy to find what a student needs, even if they have a "prospective student" link on the front page. And our college web site is as bad as most. So it pleased me a lot to see IHE pick this up in a story Wednesday.
I really like the comment objecting to the "three clicks" problem for key information, and REALLY like the person who is taking this cartoon to every meeting of a CC website revision committee meeting.
But the funniest part was the observation about pictures of "pretty girls studying under trees" on the home page.
Does your college have a photo roll including ethnically diverse but atypically good looking students studying under trees? Ours does. Using computers? (Yep) Interacting in a small group with a distinguished looking professor? (Yep) A link that takes you directly to the academic calendar or the college's majors with a clear list of requirements? (Sort of)
UPDATE:
IHE has a followup story about efforts at web redesign that starts with the student. Interesting followup. I know our college web site has been redesigned to use pull-down menus that have a laundry list of possible links, but we simply do not have a "prospective student" category nor any sense that most of the links off the front are not used.
However, I also have to wonder if "prospective" is too fancy a word for many of our incoming students, the ones that place into developmental reading classes.
The first official sign of Fall!
Today appears to be the first Student Moving Weekend.
The first hint was the sudden appearance of U-Haul trucks over the last few days, some of which might have been people clearing out at the end of July, but students were clearly moving into rental houses around the area today.
Traffic accidents and under age parties won't be far behind.
This is the second of three articles concerning calculators and mathematics triggered by a blog article by Dean Dad, a community college dean who appears to be writing from another part of the country yet has the same problems we have at our CC. I have already commented on the blogspot version of this blog (more than once), which has collected a huge number of comments, but there are also a large number of comments on the IHE version of the same posting. I'll write as if you have at least read Dean Dad's article. The discussion has been quite wide ranging, often not bothering to make a distinction between the various levels of "calculator" available to students or the many levels of math classes they might be used in. (Definitions are given here to provide a common reference.)
In this article, I will take up the specific issue raised in Dean Dad's blog and the one I know the least about as an instructor - calculators and developmental mathematics - but also look at college algebra. I'm mainly interested in putting some of my thoughts on paper and seeing feedback I get from others about their opinions of the problem.
I'll start with a particularly telling comment from Dean Dad:...part of me wonders if we’re sacrificing too much on the altar of pencil and paper. It’s great to be able to do addition in your head and long division on paper -- yes, I know, I’m old -- but is it worth flunking out huge cohorts of students because their high schools let them use calculators and we don’t?
This isn't about LETTING them use calculators. Part of it is about spending time teaching them how to use a specific brand of calculator rather than how to do algebra. However, as I wrote in my first comment on DD's blog (9:11 AM time stamp about halfway into the 50 or so comments that are there now), I think this is mostly correlation without causation. The real problem lies elsewhere.
I think the problem starts in K-5 and gets compounded by pushing kids along into the next class and lying about the content level of that class. That is, I don't believe for a minute that a student I advised had passed a REAL pre-calc class in HS just a week before I talked to her. DD writes about similar cases:...students who have passed algebra and even pre-calc in high school frequently crash and burn when they hit our developmental math, because the high schools let them use calculators and we don’t.
I don't buy it, and here is why: Our placement test will put them into Intermediate even if they can't do arithmetic, provided their algebra score is high enough. And you can't work with logarithms and exponentials or trig identities (a given if it is really pre-calc) if you can't solve a simple linear equation written symbolically like I asked the student to do.
You might forget 6 months of math in a week, the newest stuff, but not 3 years of it. And if you do forget that much that fast, you should have failed that pre-calc class. You can't get to much new material if you spend most of the year re-teaching three years of previously-taught material de novo.
K-5 Curriculum:
I don't want to belabor this, but one reason they can't do arithmetic might be that they never learned it. I'm convinced this is the biggest problem we face because it also lies behind the existence of pre-calc classes that are really teaching basic algebra. I'm sure part of it is that teachers who never understood math and hate it with a passion are teaching it by-the-book following a curriculum none of you could possibly imagine anyone would use.
My analogy is to the "look say" approach to reading, where guessing replaced phonetic decoding of words and Johnny (not to mention a cousin with a high IQ who is now an senior engineer at the VP level) couldn't read. Using guessing to construct your own mathematics might work with someone like me (I feel eternal guilt for, AFAICT, being an unwitting subject in a math ed research project that was run before the days of IRB and informed consent where they deduced that this curriculum worked really well), but it is unlikely to work with someone who was not going to get a PhD in physics. Really good algorithms were developed 12 centuries ago and survived for a reason. As is illustrated here, for the Everyday Math curriculum, the most efficient methods are not taught first or (in some cases) are not taught at all in some schools. The starting point for Dean Dad might be to get out into the feeder systems for his CC and find what they are doing in fourth and fifth grade.
If I know anything about learning, it is that students always favor the first method they get taught. (That is one reason you have to really emphasize when conservation of energy or momentum should be used instead of Newton's Laws: they learned F=ma first so it is the first thing they want to try. I'm the same way.) That means it is a really bad idea to start with an inefficient method, but which some people find useful when doing 'mental math', and teach the more efficient one last.
Now think about how to teach synthetic division or multiplication of polynomials to someone who only knows partial quotients division or the lattice method for multiplication. Not pretty. Then consider that they might never have even heard about "invert and multiply". Not pretty at all.
Outcomes:
The answer to Dean Dad's fundamental question, whether students should be allowed to use calculators in an Arithmetic class, starts at the beginning - the first step of course design. What are the desired outcomes for this math course? If the outcome is to be able to do a certain amount of arithmetic with pencil and paper (not in their heads), then the only use of a calculator is to check your own work as you make up your own problem and solve it. Ditto if the purpose is to simplify fractions involving simple whole numbers as preparation for a similar skill with symbols. You need to change the outcomes before changing what you do in the class.
Personally, I'd be happy if they taught them how to do arithmetic on their Basic calculator. Seriously! My biggest complaint when teaching physics isn't that they can't do arithmetic (they can't), it is that they can't calculate worth a damn. Digital natives my ass. I was 22 when I got my first calculator and I am faster than most of them are, and I'm slower than I used to be. (Sure, I've been using one longer than they have been alive, but that only proves they haven't used the thing enough to be competent with it.) I mean, I've watched a student work out a product by multiplying two numbers, writing it down times all of the others, entering it again !!! and multiplying it by the next, etc etc.
I know they use their calculators a lot in our Algebra (meaning College Algebra) classes, but it must all be with simple whole numbers like we used back when there were no calculators. That is the only possible explanation for their struggles with 3 and 4 digit decimal or scientific notation numbers or their mysterious belief in rounding intermediate answers.
Algebra:
There really shouldn't be many numbers in an algebra class, IMHO. Somehow the appearance of Graphing calculators changed the curriculum to emphasize numbers and, curiously, de-emphasize graphing. Since you can't actually read a graph on a TI display screen, let alone interpolate on it using a ruler, they don't appear to know how to make or read an actual graph rather than a cartoon of a graph. This is a nightmare in the physics lab, but also in the classroom when data are supplied in a graphical representation.
I don't believe anyone has tried teaching algebra with a Scientific calculator and graph paper in decades. I doubt if anyone other than the textbook and calculator companies have studied it, and studies like that are notorious for the difficulty in controlling the student mix or the instructor effect. However, stories about students who finally got algebra in a class where only symbols were used - no calculators needed - are common enough to make one wonder how it would work. The studies (see some comments toward the end) seem to lack a smoking gun in favor of the primitive Graphing calculators used today.
There is another side effect. Since they don't know how to use their calculators, particularly concerning order of operations, they use parentheses like they were the only operator known to man. ((3)(2))/((5)). One result is they don't see the key role of the parenthesis to denote "function of". I've seen calculus students who think x(t) means x*t, although this could be partly due to the fact that x is never a function in calculator-based Algebra. I have to wonder out loud if this would improve if they all used HP calculators instead of TI calculators. Also see my next comment below.
Commenting on the comments:
Some Anonymous, writing at 5:56 PM, about 3/4 of the way into the comments, writes:A kid that is getting good marks in algebra screws up their physics equations. i check with their math teacher, and they don't make those mistakes in math class. So I test them myself, and they can manage algebra just fine when x, y, and z are variables and a, b, c, and d are constants. Anything else and they're lost.
This could be a result of using graphing calculators. The TI-83 will only plot Y(X) unless it is in one of the other modes (where it is similarly limited). Parametric mode, the only place where you can do X(T), does not appear to be used at all until they get to Calc III. This really bugs a chemistry colleague, because they are always plotting the log of this versus the sqrt of that, neither of which is X or Y. Similarly, we start out in physics by plotting x on the Y axis and t on the X axis and it blows their minds. I'm tempted to start by doing only y(t) problems at the start of fall, then moving to x(t).
Mthgeek, aka timfc, writing at 7:45AM of the second day of comments, listed several references. The first of these wasThe Arithmetic Gap
I'd like to know what grade level this was, but it sounds like K-8 from the title. As for the second one that was listed, I don't ever pay attention to something like a meta analysis of 42 other papers that span middle school through calculus. Apples, oranges, confounding variables, design differences, and systematic errors make a tasty goulash but don't help with teaching Basic algebra. One other reference, discussing "computer assisted instruction" would appear to be irrelevant to this discussion. You can use computers as an instructional aid (instant HW feedback, for example) without using a graphing calculator - or any calculator at all.
Educational Leadership, v61 n5 p55 Feb 2004
Summary: The students using calculators in school classrooms result in lower math scores than students who never use them.
However, the last reference from Mthgeek is rather interesting. It is a link to an article (Refocusing Introductory College Mathematics Courses) that has a link to a new textbook (Contemporary College Algebra: Data, Functions, Modeling) that implements some of the ideas from the study. That is, the study and the textbook are closely coupled, but I recognize some things in that report that are reflected in what we do in our Intermediate class with a different book. (I'll have to ask around, but we might have made this choice because Intermediate is a pseudo-terminal course for many majors in our curriculum. The situation discussed in the article does not apply as much to our college Algebra course, because it normally leads to business calculus or trig. The statement in that report that biological sciences don't go beyond Algebra is patently false in our curriculum. They have to take Calculus even if they don't ever use it.) That said, I strongly criticize the textbook author for conflating a graph on a Graphing calculator with a graph produced on a computer. There is no comparison in detail or quality.
Some Anonymous, writing at 11:21AM on the first day, said (in part):1) middle school math is more focused on algebra as early as 7th grade. So students don't have enough mastery of fractions, percents etc
...
3) More students attending college- so the lack of good high school prep is more evident.
4) Content of dev math courses in college are aimed at preparing students for a precalc/calculus track. But those going into sociology or psychology ...
Developmental math at my CC is about preparing students for 9th grade math, not pre-calc. The Intermediate course barely prepares them for real Algebra, and certainly not for the calculus track. (Our failure rate is spectacular at every one of those steps.) Besides. students going into Psychology need a real, college-level statistics class that has college Algebra as a pre-req. Criminal Justice, on the other hand, has no real math requirements and our statistics show that the combination of our Developmental and Intermediate classes does a GREAT job of preparing them to pass the basic financial math class that constitutes their "college level" math requirement while teaching them about compound interest.
The fact that they have not learned arithmetic or fractions by the time they get to 7th grade (which is when we started Basic algebra when I was growing up) is the real problem. Three years should be enough if the curriculum and teachers were any good, but if they aren't or the kids don't learn it in 3 years, our schools track those kids away from Basic algebra for another year, or more. But this does help strengthen my point that the problem is really in the K-5 classroom.
I don't buy the "more students" argument because the fraction going to college has not changed that much in the last few decades.
Finally ...
If you have read this far, thank you. I want to close by saying that the problem really is deeply rooted in our educational system and very frustrating for all involved. The high failure rate in Developmental classes is a major problem that no one is ignoring at our CC.
However, many students fail because they never attend class, or don't attend frequently enough to engage with the instructor. With any instructor, no matter how talented ze might be. I've written about that in an old bit of wishful thinking about new student orientation. Coming straight out of HS, they believe they were taught pre-calculus or Algebra II, so they just don't believe they need to go to class and actually learn math. Older students, out of school for years or decades, know they don't remember anything from school so they take it seriously and often do quite well. An age-based breakdown of performance in Developmental classes might be worth looking at, Dean Dad.
Or Dean Dad might only need to walk by a classroom or three on a regular basis and take a sort of visual attendance. Is the room still full after 4 weeks? Maybe that, rather than calculators, is the real problem.
This cartoon from last week really captured my view of "modern" calculators. 
Click on the image to see the entire cartoon from XKCD, including the highly relevant punch line.
I was originally going to riff off of this cartoon to discuss "modern technology" in the classroom, but then Dean Dad's article came along. Just for perspective, the current model (TI-83 Plus) shows up priced between $89.99 (on sale at Staples for the new school year) and just under $100 (at Walmart and Amazon). For comparison, the CPI says $110 in 1996 will buy about $150 of normal goods today, but computer prices have been going down even as performance increases. For many decades.
Further, the cartoon is not exaggerating the connection to 1996. Today's TI-83 Plus is still running on a 6 MHz Zilog Z80 microprocessor, an 8-bit cpu that dates to the mid 1970s (as an upgrade to the legendary Intel 8080 chip). The Z80 was used in such memorable machines as the Kaypro II (running CP/M), the TRS-80, and the Sinclair and Timex notebook-sized computers. [The Kaypro, like the Osborne, was a "luggable" computer that would have to be sent in checked baggage today. I still remember using both of those.]
Not exactly MODERN technology, particularly when you consider the limitations of the 96x64 screen compared to, say, a (much smaller) iPhone. This has practical effects in that the calculator has great trouble graphing certain kinds of functions and the interface for "tracing" to a zero is really crude. More importantly, for whatever reason, I see no improvement in algebra skills associated with the month or more of time spent specifically on using this technology. Students do not use the graphs to check their answers, but that is a topic for my other postings on this topic.
Other observations:
The Plus indicates it has 512 kB of flash memory rather than 32 kB of RAM on the original model. The Silver Edition has a 15 MHz cpu and even more memory, but the added speed is one reason why you can clear its memory so much faster than on the Plus. AFAIK, the main difference is that you can clear uploaded programs on the 83 Plus but cannot clear the equivalent programs that are installed OEM on the Silver Edition. The main advantage for students is that you can connect any of these to a computer and download modestly sophisticated applications into Flash memory that are run with the Apps key.
Naive instructors believe that students have to laboriously type in crude crib sheets listing, say, trig identities or chemistry and physics formulas as fake programs. Many do this, but TI provides sophisticated, indexed crib cards - and similar tools are also available from others on the internets. Anyone who "limits" students to a note card of notes but allows a TI-83 without clearing it is laughably naive. Might as well let them bring in a notebook.
This is the first of three articles concerning calculators and mathematics triggered by a blogspot and IHE blog article by Dean Dad, a community college dean who appears to be writing from another part of the country yet has the same problems we have at our CC. The original article concerned calculator use in "developmental" math classes that typically cover fractions and 7th grade algebra. I have already commented on the blogspot version of this blog (more than once) and the two together have generated more than 80 comments. I added some more in my second article of this series.
I won't actually comment on this topic here. My purpose is solely to set the terms of the debate, as it were, because the wide-ranging discussions of this topic by Dean Dad and others are seldom clear about which of the four or more levels of "calculator" available to students are being discussed and/or which of the three or more levels of math classes (plus physics and chemistry) provides the context for the discussion.
The divisions I make are somewhat arbitrary and perhaps idiosyncratic, so I want to spell them out somewhere without cluttering up a discussion of the teaching and learning issues as I see them. That way I can link here for future discussions of this topic and not have to repeat myself.
Although I think three levels of "calculator" suffice for most classroom use, and hence for later discussion, I think I need to list at least five to make the definitions as sharp as possible.
The three in the middle, in all caps, are the ones I will refer to most often within the context of lower division classes taught at a community college.
For the record, I allow Scientific calculators in my introductory physics classes but do not allow formula sheets or cell phones or Graphing calculators to be used on exams. I encourage students to get one of the high-end Scientific calculators that can be used throughout their engineering career, including on licensing exams, so they become fluent in its use.
The four levels of mathematics classes are defined as follows:
The distinction between Developmental and Intermediate might seem unnecessary to some readers, because both levels are usually non-credit classes at a university. Indeed, some universities define college algebra as a remedial course. I make the distinction because our math department teaches classes at the Intermediate level and above, while the Developmental classes are taught by a separate department that specializes in teaching those skills. I know that smaller colleges do not make this distinction, but we are not a small college. (We have more t-t faculty in our Developmental math department than a private school like Union College has in its regular Math department.)
If I just say "Algebra", I mean College Algebra. I will say "Basic Algebra" or "Arithmetic" when I am talking about Developmental skills classes.
For the record, our Developmental classes use a Basic calculator for some things but some exams must be taken without any calculator. (The placement test and exit exam do not allow use of a calculator.) I believe they allow the use of any calculator up through a Graphing calculator when they allow a Basic one, but that might depend on the instructor. Our Intermediate classes all use calculators. Our Algebra classes require a specific Graphing calculator that is also required for statistics. Our calculus classes are a bit less picky about which Graphing calculator students can use, but ban Algebraic calculators and computers except in some special situations.
Today, June 16, is:
When looking for the official BP info about the status of the well in the gulf, I found the following comment on the Huffington Post's Social News prominently in the news stack on Google:
FREEDOM BELL(This was a comment on a Huffington Post article reporting the great news that the well had been "shut in".)
“Me either. When did Wells of BP issue email and comments during the past attempts. When did Obama ever go on TV during a past attempt?”
Equinator
85 days, 16 hours. Why was this not done the first day? All that planning to watch out for the walruses must not have helped much.
I had planned to post this a week ago (obviously), so by now Dr. Crazy has beaten me to the punch. Yes, it is that time of year, the time when you realize that next month is August! The month when classes begin. Lest we forget, the month when meetings begin! The month when there will be a number of things on the table (figuratively and literally) that you know you could have done, oh, in July. Or June.
As an inveterate procrastinator, I have used false deadlines for ages. In this case, I am now pretending we are approaching mid August rather than mid July. Those things that need to be printed for the first few labs, the ones that don't even need to have a date changed? They are going to get done this month. After all, my classes are all full (and one is overflowing) so I know what the number count is likely to be and any leftovers can be used next semester.
Syllabus for fall? Almost done, apart from one tweak and final check of the calendar and exam schedule. Syllabus for the spring? Next on my list. (Winter break is always too short.) Busy work I know I will need to do during the semester? I actually got the template updated so I only have to work on the worst part of it during the next month along with one task I have simply avoided doing for, oh, about two years.
And I plan to clean my office. Next week.
I think it was sometime in grad school, as I got to know more foreigners, that how odd it is that we celebrate "July 4th" as if a date could be the name of a holiday. (Do you have July 4th in your country? Of course, but it isn't a holiday.) Similarly, it is always celebrated as the "birth of the United States" even though it was almost 13 years later, in March 1789, that the United States government as we know it came into existence. But we don't celebrate a "constitution day" holiday like some countries do, nor do we celebrate the ultimate event that truly sealed our existence as a nation (victory in the War of 1812), although we could have celebrated two others of almost equal importance yesterday (victory at Gettysburg in 1863) or today (victory at Vicksburg, also in 1863).
So "Independence Day", or "July 4th", does multiple duty as holidays go. Including, of course, the opportunity to set off illegal fireworks while watching state-sanctioned fireworks, watching NASCAR fireworks (last night's wrecks were spectacular) and the start of the Tour de France (also featuring spectacular wrecks this morning) in HD, and dining on the least healthy food this country has to offer.
I didn't appreciate the length of the Revolutionary War or the huge gap between it and the formation of our nation until I took a middle school government class. I had a crazy radical teacher who thought we should know the real truths of the history that was behind the sound-bite myths of political speech. So I know that the Revolution War began in 1775, before we declared our independence. I remember that blew the minds of some of my classmates, but it made sense that they might have wanted to win a few skirmishes before putting it all on the line.
Ditto for the wonderful detail that George Washington wasn't the first President of the United States. There were something like a dozen of them (aha, Wiki has both the full list starting in 1774 and the ten who headed the government), each serving as the "President" of the single house of the US Congress that (weakly) governed the confederation that was the United States for 8 years, starting in March 1781 even before the Yorktown victory, negotiated the treaty of Paris in 1783 that actually granted us our independence from Britain, and developed a Constitution that would dissolve that government in favor of a stronger one.
One wonders if the United States would have been reconquered by Great Britain in 1812 if not for that stronger federal government. Ditto for surviving the unpleasantness that came along 50 years later. Would there be Spanish speaking nations of Texas and California to our west and Florida to our south if we had stuck with a Confederation that ended up a part of the UK (like Canada) or split in half across the Mason-Dixon line?
PS -
Our menu includes chili dogs, watermelon, and beer from Vermont. While you digest that, check out the great pair of videos that Unbalanced Reaction put up today. And Dr. Crazy got to watch fireworks from the porch of her new house!
Dean Dad picked up on my article of a few days ago and wrote a great followup to my followup that linked it with an e-mail request for help and an anecdote of his own. If you didn't see it, go read it now (as well as the IHE version) along with the comments. There are good ones on both sites, several of which deserve additional remarks.
Since I already posted some comments as CCPhysicist on the original DD blog, I figured I should shift over here before getting carried away in his comments section.
First, I'll include the same back link to my early writings on the "concept of prerequisites". Those came in my first wave of academic postings three years ago when I started the blog. I find that early article interesting to read because some of my views have evolved since then as I have studied it further (sadly, I think some of that is unbloggable). I should also link to the article where my readers and I came up with the idea of using basics rather than prerequisites when talking to students. However, the one area that gets more and more of my attention is the role of K-12 testing, as mentioned in the comments on DD's blog. Those, first mentioned here, have strengthened every time I talk to students about their pre-college experiences and compare the current generation of students to ones who didn't grow up in that testing culture.
But enough of that. Let's get to the new stuff.
1.
Dean Dad told this story: I recall a student I tried to advise at Proprietary U. He was several semesters into his program, and he was choosing classes for the following semester. I mentioned that course x was next in the sequence, and required for his program; he objected that it covered a software package he didn’t know. I responded that the software package was covered in the class he was currently finishing. His response, which haunts me to this day: “but that was over a month ago!” His tone suggested that I was being completely outlandish; he was just mannerly enough not to end with “duh!”
I found this fascinating because the student was still in the class that taught the prerequisite material! Presumably he still had a final exam to take, but maybe that is presuming too much about how they do things at Proprietary U. More likely it was a module on one programming tool that was tested with projects and the like before moving on to the next tool.
But I take some exception to DD's conclusion:Some of that is just a cost of doing business. Memory can play weird tricks. .... But it’s also true that thoughtful course sequencing -- which presupposes both thoughtful curricular design and steady academic advisement -- can provide reinforcement of key skills.
precisely because the student was still in the class teaching that new skill. You see, not only didn't the student know the new programming language or tool, the student didn't know it was going to be used in the next class in what I assume (from the story) was a clearly defined sequence for a "workforce" type program like ones that my CC has. I see this as an oversight by the instructor, although it could very well be the fault of the university if the instructor was a part-time adjunct who was not even aware of the curriculum. (Why else would Prof DD be advising a computer science student, given what DD says about his academic background, rather than the instructor.)
What would I recommend in this case to a colleague? First, that the subject of this programming language should be introduced by identifying when (meaning both the future classes and semesters, but also the career types) it would be used. I recommend something similar to my calculus colleagues when they introduce limits to students who "just" want to learn derivatives, and do something similar at certain key points in my physics course. Second, maybe the exam on that language should include questions about where it will be used. Hey, that is an idea for my physics class! Third, don't just say it the first day. Say it at least every week, much as I use the "this week in lab" or "next week in lab" observation to link what we are doing (or did several weeks ago) to our lab class.
2.
Several comments made explicit reference to the known fact that it is always easier to relearn something than learn it the first time. I know this quite well, but that is not the problem I am talking about here. (Hey, I too forgot lots of things along the way, so I frequently use the prompting/review example technique Cherish wrote about in the comments. Ditto for what Ivory and Lisa wrote, as well as HS lab partner of Dean Dad. I'll come back to a few of those later, since I think they are worth emphasizing just for my own future reference.) The problem I am talking about is when students have allegedly learned something several times and still don't have a grasp of it. My favorite example (listed in one of my previous articles linked up above) is the logarithm. Widely used as an essential computation tool in pre-calculator days, it remains an essential tool because exponential behavior (and, hence, exponential functions) are so common in nature. But students don't seem to really get it until the fourth time around.
We first teach it in college algebra, and I have seen the test questions used as well typical final exam questions so I know the skill level in that class. We teach it again in a pre-calculus class, where (based on the principle described above) they should just pick it back up and move on to new applications. Yet I have seen students struggling well past the end of an exam period on a pre-calculus exam that mostly contained questions just like the college algebra class. That part of the class was effectively starting from scratch. However, the ones who survive that class and log integrals in calculus seem to have learned it when I give a pop quiz on them before starting RC circuits. The fraction that survive that sequence, however, is not large. I don't think it is an exaggeration to say that the lack of even partial retention plays a key role in our retention problems in math.
3.
Gordon McAlister mentions Problem Based Learning in a comment on the IHE version of DD's blog. Although I have an aversion to Three Letter Acronym solutions to all that ails us, I tend to note that all of physics and math is problem based. The trick is what problems you choose, and what problems you put on tests. My speculation that the student in DD's anecdote was in a class built around modules comes from my experience teaching physics. IME, the worst retention results from a class where the material is tightly compartmentalized. You know, where a student taking Test 4 asks "is this like what we did on Test 2?" Every test should be part "Final Exam" in the sense of sampling key older ideas. Some of the best math profs (in the sense that I love having their students in my physics class) do this on a regular basis, and I do it also.
4.
Ivory posted a link to this critique of the mini-PhD approach to the construction of a syllabus. Yes, this is part of the problem, and it is fascinating to see a familiar problem from physics addressed in the context of a history course. It is long, but all of it (along with the comments) is worth reading. Now we don't have the political baggage they do when deciding whether the Doppler Effect is worth our time (or an exam question) compared to some other worthy subject, but it is the same problem. Clutter obscures the essential.
For me, this is a work in progress, but I will state my criteria: will someone else expect them to know this topic, or is it one where they will be expected to look up the equation that applies to a particular problem and plug in the values? Is it a skill or is it a factoid? Will their BASIC skills get better if I go a bit deeper and challenge them in a familiar area or if I take up this new topic at a very shallow level? I think the answer is that we have to deal with the reduction from 15 weeks of classes (plus exams) to 14 weeks by dropping some things that used to be thought essential. However, I am always quite up front in telling my students that I am not skipping it because no one needs to know it.
5.
Ivory also pointed to an abstract that describes one of those Increasingly Common Five Letter Acronyms (that also needs a few lower case letters) for a teaching technique. It looks to me like this was used in a course that was originally modular (if this is Tuesday, it must be Botulism). This is something that is a lot easier to do in a course like physics, and is almost identical to what a math colleague does on his calculus exams. What I find interesting is the idea of making it explicit to the students that you are doing this: that is, that you value retention of a specific subset of the earlier material. Not by talking about it, but by testing on it.
Definitely something to think about in a survey course where this is rarely done.
But you know something? The humanities courses where I really retained the material (and that make visiting museums a joy) were ones where there was a unifying theme in the interpretation of disparate items. That made you look for patterns as new things showed up, and LOOKING is the first step to real learning. You don't learn if it just washes over you like a rogue wave.
Perhaps you saw the news stories reporting many complaints about signal loss on the new Apple iPhone 4? (Here is one from yesterday.)
As I guessed, the problem is not with the antenna itself, but the fact that there are two antennas on the phone, separated by a small distance on the case. (See this news story, among others, on what the user must not do and how to fix it.)
The problem is that humans conduct electricity. No problem if there is only one antenna, since that just makes you part of the antenna if you touch it. The problem arises when the user short circuits the gap between the two antennas by touching both sides at the same time. (That means a quick fix would be a bit of electrical tape around that corner until you get the more expensive, but better looking, plastic or rubber case mentioned in the articles.) And since MSNBC does not have a physicist in the news room ... I'll add that connecting the cell and network antennas certainly could explain the problem.
It changes the tuning of both antennas, which is bad enough, but it also means that one poor antenna is feeding two separate receiver circuits rather than each one getting its own signal. It would also short the transmitted signal from one side into the input for the other side, reducing the energy that goes out of the antenna to the cell tower. I have no clue at all what those circuits look like, but a decent impedance match could kill the outgoing signal needed to keep the "line" to the cell tower open.
I don't have one or I would do the simple experiment of shorting the gap with a potentiometer to watch what happens as the gap resistance varies.
A great new job-related series, this one oriented toward faculty at research-intensive institutions, has started up at IHE. Here is the link to the Academic Jungle index at IHE and to the first article, about the importance of service in the R1 world.
The same article appears in the home blog of the author, GMP. (BTW, "geek mommy prof" is a great nom-de-blog.) It makes the important point that you can't afford to zero out any part of the research/teaching/service triangle. It is sort of a counter-point to the emphasis I put on outside letters in Part 4 of my jobs series, which focused on R1 faculty jobs from the viewpoint of an outside observer.
(I was going to post some of the following additional comments on that blog, but for some reason Firefox does not play well with that particular comment form - so I'll put them here.) One of the comments over there had to do with teaching-intensive jobs. From my viewpoint, it is more than just a matter of flipping research and teaching. As I elaborated in Part 5, we expect a formal teaching portfolio, or its equivalent. Just as you might not know about outside letters until last in the tenure process at an R1, you might not know anything about teaching portfolio if you come out of a research university - which is the case for just about everyone looking for a teaching job.
I'll add that there might be more jobs out there than "Alyssa" knows about, because many teaching jobs are simply not advertised in the same place as research jobs.
I'm going to try again to comment on GMP's sited, but one reason I didn't comment on the IHE version of the article is that I don't like to dump a bunch of self-serving links on their site. But I have no problem doing that here. All of my articles related to jobs (some clearly about physics, but others not at all) can be found in this link summary. In addition to the two mentioned above, I think this one (linking to an IHE career advice column by a female mechanical engineer) is really good for R1 jobs because that article makes many strong points, including one about presenting your case so the inevitable holes are less visible. On the teaching side, this one riffs off of a great article by Dr. Crazy (showing that teaching Physics and English can have something in common) and makes the point about keeping useful records.
Good record keeping, meaning a good process, is essential if you want to document all of the service you have done. No one can do that for you. I use a small calendar whose sole purpose is to document "odd ball" stuff that has to go in my annual evaluation -- and I already have tenure.
Dean Dad always has great, thought-provoking blog posts, but today's blog rates a double comment.
First, it really shows the importance of having academic leadership (Dean, Provost) at a CC come out of the ranks of teaching faculty at a CC or comparable institution. (The key issues are different at a research intensive university, but the same principle applies there precisely because the key issues are different.) If Dean Dad the Professor had not had dealt with the question of a perceived conflict between passing rates in a given course and weak students who pass that course, Dean Dad the Dean might not have identified the middle ground he so succinctly describes in his blog.
Second, it identifies what I think is a key issue at any college: getting across the idea that prerequisites have real significance. As you can tell if you follow that link, I've written a lot on the subject. A couple years ago we (meaning my blog readers and I) came to conclusion that COLLEGE-LEVEL BASICS is a better term to use when describing pre-req skills. I have started using it, and have found it a helpful way to get the idea across to the upper level students taking calc-based physics, students who don't think of calculus as a basic skill.
I already posted some comments on the blog article itself under my nom-de-comment of CCPhysicist. My main observation is that the best way to define appropriately high standards for a course is by making it your objective that they leave one course prepared to pass the NEXT one.
IMHO, this is partly a matter of setting high standards from the first day of class and partly a matter of conveying (that is, getting them to absorb into their core beliefs) the radical idea that specific parts of the new and challenging material in my course are actually basic skills. Indeed, I think this second part is more important than the first.
Why?
One of the things we (meaning me and my colleagues who teach calculus and trig) talk about regularly is the fact that we all know that certain students knew skill "X" when they passed the previous class - including my own - and forget it within a month. We have to do our best to ensure that we each know that such regular occurrences are not the fault of the instructor, since we can't evaluate what happens a month later, and yet work on ways to reduce how often those situations occur. When I have control, like when students from my own Physics 1 class don't remember to draw a free-body diagram in Physics 2, I make it clear that the failure is completely unacceptable. That if they keep up that practice, they will be laughed at as "community college losers" when they get to engineering school.
(Now, I happen to know - from my graduates - that it is far more common that the university students are the ones who show up with heads empty of knowledge that they paid thousands of dollars to allegedly learn, but that is only because the ones who come back and visit didn't screw up less than a month after taking Physics 1. They learned it the first time. I'm working on getting some of them to talk to my class early in the semester. Students listen to other students more than they listen to us.)
It is not an easy battle. It has to be fought anew every semester. I have learned to make it a habit to mention where some skill will be used in a course next year. I have made it my mission to learn where those places are, by visiting my former students at nearby Wannabe Flagship. I share what I learn with my math colleagues. (What calculus did you use last semester?) Now that summer is here, I plan to head over there in my spare time. The people who teach physics at Wannabe Flagship are much closer than I am, but I doubt if they ever see their students again. They are rewarded for that. Well, neither am I (there are no performance bonuses in our pay system), but I get my reward every time I see the success of students who started out at our CC, particularly the ones who started out a year or more behind the kids at Wannabe Flagship, sometimes in developmental classes.
So, if someone at a university is reading this, visit a different building once in a while and talk about teaching rather than research or university politics. Find out what your students didn't retain, and share what theirs didn't retain. It can't be about blame. I've seen cases where you can document that a student did it perfectly on a final exam one week and could do nothing on the same problem a month later. Heck, I've done it. But only once. One thing I tell my students is to pay attention when they see something a second time. If you don't remember it, make sure you learn it permanently the second time. Anything that gets used in two classes is likely to be used in all of the rest.
To conclude, I want to draw on an example from the comments on Dean Dad's blog. Anonymous wrote at 10:30 AM:the blame falls to the students for their own inability to learn the course material. They had me, a book, and any previous experience to fall back on (including Comp I and possibly II). Some students do not want to rise to any level that requires work.
The last statement is true, but that might not be the problem. Talk to the person who taught Comp I to a particular student. (At our CC, this is easy to look up but YMMV.) Or ask other students what they did in a particular Comp I class. It could be that the reason they can't "craft a thesis statement and defend it with evidence" is that this was not part of their class. Or it could be that they had learned in HS that each class will teach that skill all over again if it is needed, so there is no reason to learn it. That other teacher might not be able to solve the problem either, but together the two of you might effect a change for the better by the time they take a third class. At some point they need to learn we teach certain things for a good reason.
Or you might learn that the Comp 1 prof used oral presentations in class as a substitute for written work. Ah, the stories students tell other students when they think professors are invisible and deaf ...
I've been busy commenting on my fave blogs for the last few months rather than post here, but it is time to correct that oversight.
There was a great question, about teaching summer classes, posted Saturday in the unbalanced reaction blog:
Some of my colleagues complained nearly nonstop through the first summer term. I wonder, is summer teaching REALLY that bad?
Either that or they are utterly innumerate or so blinded by racism that they can't tell the difference between the number 12 and the number 10.
Our taxes went down a lot this year compared to last, with almost no change at all in our income level and without benefiting from any of the "special" tax cuts in the ARRA plan (sales tax on a new vehicle or downpayment on a new house).
How much?
Most years I calculate an effective tax rate by dividing the income taxes due by the total income (bottom line on the front page of form 1040). It gives a sense of what my "flat rate" tax would be if income was taxed in the same way the FICA tax is figured. The result?
Last year we paid almost 12.4 % of our income in "income tax", while this year we paid less than 10.9 %. That is more than a 10% drop in our taxes whether you figure it from the percentages or the actual dollars paid. So I say "Thank you Pres. Obama, Sen. Reid, and Rep. Pelosi for cutting my taxes" even though we make well over the median family income for our area.
What didn't go down? We still pay (between out of my pocket and out of the pocket my employer pays me from) over 15% in FICA and Medicare taxes, a rate far higher than our income tax rate. Further, we pay (again between out of pocket and out of employer's pocket) about 12% for health insurance, even before you total up co-pays, which is a bit more than we pay in income taxes.
Conclusion:
Between Social Security taxes, Health "taxes", and Income taxes, our income tax rate is the lowest of the three. (Our state and local taxes are much smaller than any of those three.) Given our income bracket, this should also be true for more than half of the US population.
Interesting story about using lasers to clean artwork from the BBC this weekend.
This application (and its cousin, removing tattoos) didn't make it into Chad's laser smackdown, but it is an interesting combination of applied physics and chemistry.
What was interesting to me was that they have had to design lasers with the specific frequency needed so the energy gets deposited in the grime rather than the paint of the frescoes they are using it on, and also research the duration of the pulse so the damage is limited to the undesirable material and not the pigments or surface coating on the wall.
What struck me as really clever was using a laser underwater to do in situ cleaning of a coin in a shipwreck. It must be really useful to identify the value of an archaeological site without having to excavate a found object and bring it back to the lab.
Surreal, or real?
From the latest installment (Cecilia in Thesisland, Part 6) of an ongoing series by Jorge Cham's cartoon blog Piled Higher & Deeper, we find
Click on the image or the link above to go to the full cartoon.
What a wonderful combination of the reality of dealing with teaching duties while working on your dissertation and the daily reality of dealing with undergrads!
Well, not my daily reality. This (and the even better situations in other panels) only happens because other faculty send the message early and often that they will give credit where it is not due. It doesn't take long before students realize you mean every word in the syllabus, particularly if you give a quiz on the first day of class that asks them to find the place in the syllabus where you say how they can earn extra credit in the class.
Sure you can go to that wedding. That invitation will explain why you missed the first (and easiest) test of the year and will have to use that zero as the one exam you get to drop, but a wedding does not excuse you from having to learn the material.
