Entry Points and Resource Allocation

Over in locked LiveJournal land, I read a post talking about computer science education, and how it’s biased against people who aren’t already tech geeks coming into college:

Taking an intro CS course if you don’t already know how to program is like taking intro Spanish without ever having taken it in high school – 90% of the people in that class are ahead of you, possibly way ahead of you, on day one, and you’re working from the back.

That is a brutal situation to be in, honestly, and it does nobody any favours. The people who don’t already know how to program are dealt a crushing blow to their confidence while taking an already-difficult class, and are probably just going to drop. The people who do already know how to program are going to receive another shot of self-confidence, which they almost certainly do not need, due to them being arrogant little shits as it is, and this will just put off the day when they finally realize that they are mortal.

Which is why I’m surprised that it’s not absolutely standard to have, like, a 5-credit “Intro to CS” for non-programmers and a 3-credit one for people who feel they already know how to program. It seems like a straightforward idea, segregate people into groups based on experience, and spend more times drilling stuff into the people who need to learn it all from scratch, right?

This is a problem that afflicts a lot of technical fields. We hit something fairly similar in physics, where the background assumption of even the intro classes is that students have seen some of this stuff before. This is a reasonably good assumption from a statistical point of view– I ask every year, and the vast majority of the intro students have had physics in high school– but it kind of sucks to be on the wrong side of it.

The idea of providing multiple points of entry is a good one, and it comes up a lot, but it’s not general practice because the implementation details tend to be a real bear. In the end, most departments don’t do this because the staffing and resource demands are judged to be too great for the expected payoff.

There are a bunch of problems posed by having different tracks of introductory classes. First, you need a good way to sort students into the appropriate groups– you won’t get anywhere near a reasonable sort by asking students to do it themselves. Years of psychological research show that the most clueless people tend to be clueless about their own cluelessness, and will stubbornly insist that they really belong in whchever group is deemed more advanced.

You can get around this with placement tests and the like, and that works reasonably well for some subjects. Union’s Math department offers three different versions of the intro calculus curriculum, and sorts students into them primarily based on AP test scores. This runs afoul of inequalities in the high school educational system at some point, though– students who went to schools that didn’t offer AP classes, or who couldn’t afford to take the exams get shut out.

You can also do a placement test, which is the approach the Chemistry department at Union uses to sort students between the couple of different versions of intro chemistry that they offer. All students attempting to take intro chemistry need to take a local placement test, and their score on that test determines which sections they’re allowed to take. This also requires a good deal of effort to implement, at least at first– you have to draw up a reasonable test, and work out a way to administer and score it in a timely manner.

Once you get the students sorted into the different sections, you need to be careful to synchronize the different intro options. A key element of this sort of scheme is that the two introductory streams need to be merged at some point, and if they haven’t done the same things before that point, it just pushes the problem back a level. For several years now we have offered an honors section of the two intro classes, and I taught the next course in the major sequence a few times when the honors and non-honors sections were operating on very different curricula, and it’s not a very good situation. While both courses covered broadly the same material, they took a very different slant on it, which meant I couldn’t assume the students knew the material of either track– I had to teach it as if the subject were totally new to both groups. Which meant that each group spent a week or so being bored by my reviewing stuff they already knew how to do, but that the other group had never seen before. (The alternative being each group spending a week or so totally at sea while they tried to figure out stuff that the other group had seen before, which would completely defeat the purpose of the different tracking.)

And, of course, you need to be careful to avoid stigmatizing one track or the other. If the different flavors of the intro course carry different numbers of credits,

Then there’s the staffing question, which particularly affects small departments. When you split off a different track of the introductory sequence, you need somebody to teach that, and someplace to teach it. If your normal intro sequence is a large lecture taught by a single professor, that means creating two separate lectures taught by two people, which means pulling a faculty member off some other course that then doesn’t get offered. If you’re talking about a lab science, this also means tying up some teaching lab space for the new track, which may have very different lab schedules or requirements. When space is tight, that can be a real deal-breaker.

And then, of course, there’s the question of what payoff you get for this. We do occasionally have students register for our introductory classes who have absolutely no high school physics, but there aren’t many of them, and very few of them are interested in the major. Now, you can argue that setting up a new introductory class would create a new audience for that sort of thing– that’s the whole idea behind the different tracks, after all: that providing a different approach would make the subject more attractive to a wider range of students– but it’s a big investment of resources to make based on hope.

In the end, most departments do a bit of this sort of thing already– in physics, basically every department in the country offers an alternative introductory track aimed at students who don’t want to major in physics, but who need it for the MCAT. That provides a consistent enough demand to justify the commitment of lab and faculty resources, and ducks the problem of synchronization by not feeding into the regular major track at all. That’s about as much tracking as is practical for physics. I suspect, but am not entirely sure, that there’s something similar at work behind the different tracks in the other departments that have them– the Math department has to provide some courses that are accessible to essentially every entering student, and the Chemistry department also gets a lot of students who don’t want to be chemistry majors, but need to take enough chemistry to meet med school requirements. Setting up completely different entry points for the major track, though, is a much bigger deal than you might think right off.

(It should be noted that this is largely a matter of the hierarchical nature of science, where you need a fairly specific knowledge of some basic subjects before you can go on to more advanced topics. It’s relatively common to see multiple entry tracks in the humanities and social sciences, but then, if you want to major in, say, African history, you don’t necessarily need to know anything about American history, so you can set up a sequence that appeals to students who want to know about Africa without knowing about America, and another that appeals to students who only want to know about Asia and not Europe, and so on. That doesn’t work as well in science– even if you want to do astrophysics and not atomic physics, you need to know enough quantum mechanics to understand spectroscopy, and so on.)

This is not to say that something like this can’t be done– in fact, the CS department at Union has recently redone the intro sequence to provide several different flavors of the introductory course, for students with different particular interests. That’s not exactly what the original poster was asking for, but it’s pretty close. I’m not sure how that change is playing out, though– it’s fairly recent, and my knowledge is only second-hand. I don’t know if it’s led to more majors, or to a more pleasant major-track experience for students who don’t already come in as tech geeks. It does represent a significant re-working of the way things re done, though, and it’s not something any department would undertake lightly.

A more common approach is to try to re-think the single introductory sequence so as to provide an experience that is different enough from the the high school curriculum to present a challenge to those with reasonably good backgrounds in the subject, while also being paced slowly enough to be accessible to students without any background. That’s the thinking behind things like the Matter and Interactions curriculum we’re using now. Whether it’s successful or not is a subject for another long and rambling post at some later time.

22 thoughts on “Entry Points and Resource Allocation

  1. I don’t know where that person went to school, but that was just not the case at Stanford. There WERE two intro courses, one totaling 10 units and specifically for people who didn’t have any kind of experience, and the other 5 for people who did. I took the first course and got a solid A, I even came close to winning an in-course contest (out of hundreds of people taking the course). The same thing was true for Spanish (the intro courses varied in length depending on experience).

    So, basically, this person is talking out their ass. Or being way, way overly broad. Either way, they’re wrong that this is a universal phenomenon.

  2. The hierarchical nature you describe is not limited to science. Languages work that way too. You need to learn basic grammar and vocabulary before you’re able to tackle novels. (And if the language has a different alphabet, there’s a whole other step involved.) Most language programs that I’m aware of do have a placement system: they expect students to arrive with various levels of proficiency. And I don’t know of any college with a language program that doesn’t have classes for someone who has no knowledge whatsoever in the language.

    Now language classes tend to be smaller, as a whole, than introductory science classes. But I think there’s a real focus in schools on teaching a new language from scratch to people interested, even if they’re not interested in majoring in the language. Given the hand-wringing we’re facing because of the poor levels of science education in the U.S., I wonder if the science educators might benefit from that approach as well. (I do understand the costs, but I think there’s a whole lot of benefit not accounted for in your analysis.)

  3. In the intro to computer science courses I took, they got around the problem by teaching everyone Scheme, a computer language so different in syntax and basic concepts from procedural languages like C that everyone was starting from scratch. I don’t know if a similar strategy could even be devised for physics classes, though.

  4. Stuart @ #1-

    Here’s a life lesson for you: don’t assume that all, or even most of higher education resembles Stanford.

  5. The “different enough from high school” can be done to great effect in math by using Spivak’s Calculus. That’s what my undergrad did for the ‘honors’ calculus section and it really helped even out the varying levels of experience, at least between those interested in math.

  6. Andy @3:

    1) Anyone who has seen recursion before has a significant advantage learning Scheme.

    2) Anyone who has done enough mathematics to think of functions as first class objects (a viewpoint I think every proper Calculus class should provide) has a significant advantage learning Scheme.

    So teaching Scheme doesn’t change the fact that some students have an advantage based on prior background; it just shifts around who has advantages.

  7. I can’t speak to the situation at Union, or SLACs in general, but the universities I have been affiliated with (both private and public) all offer or have offered some kind of honors track in introductory mechanics/E&M. Only one of them, to my knowledge, offers a distinct physics for pre-meds track (my undergraduate alma mater requires the regular track physics for science and engineering majors even for students majoring in humanities and social sciences). It’s just a question of resources.

    One trick that my undergraduate alma mater used was to arrange for all of the first-year calculus course lectures to meet at the same time, so if a student discovered three or four weeks in that he had selected too high a level he could retreat to the lower level course without too much difficulty.

    Also, I second Alice@2’s comments re: foreign languages. My high school had to solve that problem as well; we had a substantial population of middle to upper class Hispanic students who obviously knew too much about the language (formally as well as spoken) to start out in Spanish I. Some were even advanced enough to place at what would be the AP level for us gringos (and had a trial by fire as several of them had never taken such an academically rigorous class before).

  8. Alexander Woo @6:

    There will always be someone with an advantage – even if that advantage is simple being more intelligent, or a faster learner. Not all students are created equal.

    In general, the goal isn’t to cripple gifted students to the point where all students get Cs. It’s to create classes where everyone comes out learning. Teaching Scheme means that more students will learn something they didn’t previously know.

  9. Unless it’s changed since I went there (a quick look at the course descriptions suggests it hasn’t), the problem the chem. department is trying to solve is a bit different from the one noted by Chad. It does have some similarities, though.

    Chad mentions the problem with having students who have no high school physics in class with students who have had some high school physics. Unless things have changed, the Union chem. department lumps all these students together.

    At the other end, you have the students who have taken two years worth of chemistry in high school, with the second one typically being AP. You can’t reasonable expect that one AP course is equivalent to two college courses, so it would be hard to justify having them skip both introductory courses. Many departments approach this by putting the students with AP credit into second semester chemistry. When I was there, the physics department solved a similar situation by putting students who had taken AP into second semester physics.

    The problem is, AP chem doesn’t just cover the 1st semester material, it covers material from both semesters. The Union chem. department approach is to have a third course designed mostly to fill in any gaps, especially in lab.

  10. Alexander Woo @6:

    Regarding (1), I agree recursion is very helpful for understanding Scheme, but it’s underutilized by most partly self-taught students, which is what you usually get in the sort of 100-level class I was referring to. They generally don’t understand it well.

    As for (2), I’m pretty sure we never discussed the different meanings of the word “function” in my calculus classes, regardless of whether we should or shouldn’t have. (For that matter, there’s also the issue of the multiple meanings of the equals sign in mathematics, which is even more fundamental.)

    Taking the two points together, only a very tiny portion of my CS class had any real advantage learning Scheme. There WERE still differences, but they were actually because people with prior programming experience were better at formulating algorithms to solve the assigned problems, which is a skill that’s somewhat independent of programming language. Overall I think it was a successful strategy for evening out differences in prior experience. People started from a slightly tilted playing field instead of a near-vertical field (to mangle a metaphor).

  11. Eric @7

    They may not refer to them as for pre-med and not, but my experience has been that there are typically least two tracks of physics: one calculus-based and one algebra based. (That’s in addition to any strictly gen-ed type classes). The algebra-based may not be officially “premed,” but it is usually all that’s necessary for med school and for a biology major, so a lot of the students taking it will be premed. The physical sciences generally require the calculus-based class.

    It’s anecdotal, but all 4 of the colleges I’ve been at have had both an algebra-based track and a calculus based track. Given the range of schools (large public R1, small private R1, medium public masters-level, and small private all undergrad) and that all of them had the same system, I think it’s reasonable to assume that it is at least not rare.

  12. There is already a fix for this: junior college. A given university should set some basic standards for what incoming students should know. If the students don’t have that knowledge, they should go to a different institution.

    I am not saying this to be snobby or mean. Rather, I think most other people’s snobbishness has averted them from this perfectly good option. Or maybe I should blame the newly popular concept that “everyone” should go to a university and they need to start there, and there’s something “wrong” if you don’t.

    I disagree with this viewpoint: I teach at a large public university, and some of my best students started their careers at our local 2-year community college. (Some came from rural areas and didn’t have enough prep for university, some were trying to save money.) Similarly, a graduate student I met in the physics department of an ivy-league school started his career at a junior college.

    If the vast majority of the students start WAY ahead of you and you can’t catch up, then you may be at the wrong institution. No institution can be all things to all people.

    If the original poster wishes to assign blame, perhaps he should blame admissions for letting him in?

  13. I agree totally with AC above about community colleges. I went to one, then got a B.A. & Ph.D. at a “research university” and now teach at a CC (best job I’ve ever had in academia and that includes SLACs like Union). Another option at most state universities for people interested in physics but with no HS background is to take the intro courses that are usually set up for engineering majors. These are usually populated by engineering majors who are sophomores or juniors, so that can be tough competition, but it’s better than starting out in the class for people on a physics track (which is sometimes an “honors” class). Most state universities usually have a “non-calculus” pre-med physics class too, also usually populated by juniors. It’s a cliche’ that these classes are cut-throat (because they are) but do well enough to impress your prof, and most places will let you transfer to the physics track (dirty little secret of most intro physics classes, even the “honors” ones, is that very little calculus is actually needed to do well). I’ve taught all those classes btw, so I’m not just making stuff up…..

  14. Anonymous Coward–

    You’re skippng the question of what should be considered necessary for university admission, though. You seem to be assuming that it’s a certain amount of math, physics, and/or chemistry. So, in your system, the person who is bilingual and strong in history, but whose school didn’t offer calculus or chemistry, might have to go to junior college for a year first. What about the person who knows calculus and can program in Java, but can barely write an English paragraph, let alone one in any other language, and doesn’t realize that there’s anything between the American Revolution and Y2K?

    It’s easy to assume that one’s own particular discipline is most important; however, a university admissions department is not, or should not be, a subsidiary of the physics department. Or the English literature department. Or math, programming, or Romance languages.

  15. Vicki-

    What’s necessary for university admission depends on the university, of course. UC Berkeley should have different standards than Cal State Sacramento. (My institution is much closer to the latter than the former.)

    I’m not assuming math and science are the only prerequisites; it’s what I mentioned because it’s what I’m most familiar with. In response to your question, I consider your second hypothetical person as much more poorly prepared for university than your first. Not being able to write an English paragraph is a sufficiently serious deficiency in terms of preparation that such a person should not go to a college that doesn’t offer remedial English. And I think it’s perfectly fine that SOME colleges don’t offer remedial English. Surely you’re not suggesting that a nation’s most selective universities need to accommodate those who are borderline illiterate?

    And what if either of your examples go to a junior college to increase their competitiveness in later classes? Do you think there’s anything wrong or shameful with that? I don’t, and I have great respect for those who have followed that path to success.

    We have a system where certain things are taught at certain levels and institutions. If we try to make it such that EVERYTHING is taught at every level and institution, we will wind up with a much weaker system (for reasons Chad mentioned). Most large public universities are already quite accommodating of those with a wide variety of backgrounds and preparations. If SOME universities aren’t, I think that’s OK.

  16. The problem with two tracks is that some students will invariably try to game the system. They’ll take the gentle introduction despite having plenty of programming experience; easier class _and_ two extra credits; what’s not to like?

    My old university math department had a slightly different approach: a non-credit, completely voluntary three-week summer class that went through all high-school level math up to the point needed for the uni introduction course.

    The Spanish department had a different approach, as I heard it: if you didn’t already know some Spanish (from taking three years during high school for instance) you were not welcome. They’d suggest you take evening classes for a year or perhaps study something in Spain for a semester before reapplying the next year. Of course, that department was (is?) famous for being a dysfunctional mess so I have no idea if this is common or just their idiosyncratic approach to learning.

  17. I’m clearly not understanding the problem, here.

    If the “into to CS” class is not in some form or another an entry level programming course, then what on earth would it be? And every university I have ever attended has had at least one course of that nature, in the approved language of the CS department. Often, they’ll have more than one, for different languages.

  18. andre3 @ 4: chip on your shoulder much? Anyway, my undergrad school (not Stanford) had multiple entry points for CS, and I haven’t seen anybody putting out any evidence that either single or multiple entry points are more common.

  19. There is, in the US, a strong belief in new beginnings: that anyone can start over, in a new environment, without penalty. This is a wonderful thing in a society, but it makes university/college teaching difficult.

    I grew up in England, where there is no such belief. The system has been somewhat liberalized since my day, but I think it is still true that one cannot study a scientific subject at university without having chosen, at the age of 15 or 16, the “science side” at school. University admissions are to a major (or often to a concentration withing a major) and are based on results in A-level exams in three or four subjects. Someone wanting to be admitted to a physics course of study will have to have taken at least physics at A-level (and probably gotten at least a B in the exam) and probably two other scientific subjects. People teaching the freshman courses can make fairly good assumptions about what their students know.

  20. The tracks that I remember, particularly for physics, were not based upon background, but what the students field of study demanded. We had one for Physics, and Astronomy majors (with a couple of honours math & engineering students jumping in for a challenge). Another track for science majors, and a third for general Ed. At least where I went honours students could pretty much pick a course, and sink or swim based upon their choice and ability.

    I do see the CS thing though, my freshmen son, (a CS major) was required to take the intro course, even with a good AP score, but was allowed to take two final exams, (one for the first course, and one for the second), so he was allowed to skip one. Still, I think it hurts students on either end of the scale (knowing too little on day one has got to be tough, but knowing too much is at best a waste).

  21. So universities are supposed to be burdened with teaching high-school level “intro” courses? Seems like a waste of academic resources. PhD professors are not needed for this.

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