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2013 August 14

Service courses

Filed under: Circuits course — gasstationwithoutpumps @ 22:36
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Joe Redish, in his blog The Unabashed Academic: wrote a post On service courses, in which he talked about a physics course he teaches, recognizing that the primary audience is not physics majors:

In physics departments, a lot of the students we teach are not going to be physics majors.  They are going to be engineers, chemists, computer scientists, biologists, and doctors.  Everybody (that is, all physicists) agrees that physics is good for all future scientists since physics is the basis of all other sciences—at least that’s the way it seems to physicists.

 He added that they wanted to take my course, despite the fact that they were biology majors and therefore it wasn’t of much relevance for them.

Well!  Despite the fact that I had thought carefully about what might be useful for biologists in their future careers, and focused on developing deep scientific thinking skills, it suddenly became clear that I had failed in an important part of my goal.  I had managed to teach some good knowledge and good thinking skills, but I had not made the connection for my students to the role of that knowledge or those skills in their future careers as biologists or medical professionals.  The occasional problem I had included with a biological or medical context did not suffice.

I therefore propose we who are delivering service courses for other scientists—and I mean mathematicians, chemists, and computer scientists as well as physicists—ought to measure our success not just by the scientific knowledge and skills that our students demonstrate, but by their perception of their value to themselves as future professionals.  We can tell ourselves, “Well, they’ll see later how useful all this is,” and they might, but that is really wishful thinking on our part.  If our students see that what we provide is valuable now, they will maintain and build on what they have learned in our classes.  Otherwise, it is likely that what we have taught will fade and our efforts will have been largely in vain.

I wish our faculty who taught service courses thought about their classes this way.  All too often I hear from students that they don’t remember anything from the required science classes, and that the faculty who taught those courses did not care whether they learned anything or not—both students and faculty were just going through the motions without any real teaching or learning taking place.

I’ve never taught a large service course for students outside my department (though my department has changed, I’ve always focused on courses that were very directly related to the major, even when teaching lower-division courses like Applied Discrete Math).  So I can’t speak from experience about teaching students who see no point to learning the content of the course—it must be tough.

About the closest I’ve come is in teaching tech writing, which I instituted as a requirement for computer engineering majors back in 1987.  That course was not one students enjoyed much (there was a huge amount of writing, and a corresponding huge grading load), and many saw it as well outside their area of competence (and for some, it was).  But even the tech writing course was carefully tailored for relevance to the engineers taking it. Every assignment I created was intended to develop skills that they could use as engineers and as students.

I’ve had people come up to me and tell me that they took the course from me 20 years ago (I rarely remember them), and that it was one of the most valuable courses they had in college—which is gratifying to hear, since few of them wanted to take it when they were students.

It is possible to make courses that seem outside the students’ interest relevant, but it takes some serious effort.  I think I managed to do that with the Applied Circuits for Bioengineers course that I prototyped last Winter and will be teaching again this coming Spring.  None of the students in the course were interested in bioelectronics—they had all put off the required circuits course as long as they could, because they were not interested in the material and had heard horror stories about how dry and difficult the EE course was.  By the end of the quarter, several of them were excited about what they could do with electronics, and wishing they had been able to take the course much earlier—they might have chosen bioelectronics instead of biomolecular engineering as their concentration.  The standard circuits course had squelched almost all interest in bioelectronics—only about 1 out of 20 or 30 bioengineering students had been choosing the bioelectronics concentration, and he was going on to do radio electronics for an MS degree, thanks to a particularly good lab instructor in EE.

It is never enough, even in a course for majors, to design the course around “they’ll need this later”.  It is far better to make them want to know it now, for things that they can do now.  For the Applied Circuits course, I concentrated ton the students doing design and construction in the labs, with just enough theory to do the design.  This is a big contrast to the traditional circuits course, which is all theory and math which EE students will use “later”—totally useless if the students then never take another EE course.

This year I hope to replace the requirement for the EE circuits course in the bioengineering major with a requirement for the applied circuits course.  Those who want to do bioelectronics will still have to take the EE circuits course, but they’ll go into it knowing half the material, and knowing what the theory is for, which should move the bioengineers from the bottom of the circuits course to the top.

I wish I had the capability to replace the chemistry and physics courses also, but I’m not aware of tenure-track faculty in either department who are interested in changing what and how they teach for students outside their own major.  Note that for the circuits course I could not get the EE department to teach the course that was needed—I had to teach myself circuits and design the course myself (which took me about 6 months full time).  And I was a lot closer to knowing circuits (from my experience in teaching digital logic and VLSI design) than I am to knowing chemistry (which the least serviceable service course that we require of bioengineers).

One thing that chemists and physicists could do to make their courses more useful and interesting to engineering students is to put design into the labs.  Engineers want to make things, not just study them.  Far too many of the freshman science labs are cookbook labs, where the students are just taught to follow carefully written instructions to make a series of measurements to get an answer to a question that they weren’t interested in to begin with.  What a waste of precious lab space and time.

2013 May 16

Storytelling to close the gender gap?

Filed under: Uncategorized — gasstationwithoutpumps @ 10:19
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In Closing the Gender Gap in STEM Fields With Stories, Bethany Johnsen wrote an

Making science classes more “like that” is also the suggestion of a recent Scientific American blog post, To Attract More Girls to STEM, Bring More Storytelling to Science. Its authors, teachers at a STEM-focused high school, argue that the reason for the gender gap in the STEM fields is not a shortage of girls with ability, but the failure of our science curriculum to engage their interest and kindle their passion. The remedy they propose—telling the stories of science—could lend the STEM fields some of the allure traditionally left to the humanities.

While I agree that the shortage of women in STEM fields is not due to a shortage of girls with ability (the dominance of girls at middle school and high school science fairs is clear), I’m not convinced that a story-based approach is going to work. History of science is not science, and stories about scientists are not science. Replacing science instruction in middle and high school with stories and history would leave students less prepared to study and do real science, and more likely to choose a humanities field in college.

Note that there isn’t a gender gap in biology (at least not through grad school—there is still some gender gap in paid jobs), so the problem isn’t with “STEM” as a whole, but more specifically with the math and computation-based STEM fields.  Even among those fields, there are wide disparities, with math itself coming much closer to parity than physics or computer science.  Why?  Is it something about the field, about the way the field is taught, about the culture of the practitioners, or about the culture of the students currently majoring in those fields?

Making the science instruction more interesting is a good goal, but the suggestion of the SciAm blog post “How many engineering teachers include a fiction book like Kurt Vonnegut’s Player Piano in their syllabi?” seems to me to miss the point.  Replacing science and engineering with fiction reading will not result in more students studying engineering and science—it will result in students studying literature and thinking that they are studying science.

The basic idea—to use a more story-telling approach to teaching STEM—is a good one, but I think that the stories have to be intrinsic to the science and math, like Dan Meyer’s The Three Acts Of A Mathematical Story, not stories about science, which seems to be what both blogs are advocating.

I don’t know how successful approaches like “Storytelling Alice” have been—it is no longer available though the web page claims it was successful:

A study comparing middle school girls’ experiences with learning to program in Storytelling Alice and in a version of Alice without storytelling features (Generic Alice) showed that:

  • Users of Storytelling Alice spent 42% more time programming than users of Generic Alice.
  • Users of Storytelling Alice were more than three times as likely to sneak extra time to work on their programs as users of Generic Alice (51% of Storytelling Alice users vs. 16% of Generic Alice users snuck extra time to program).
  • Despite the focus on making programming more fun, users of Storytelling Alice were just as successful at learning basic programming concepts as users of Generic Alice.

Of course, Alice is not the most fun programming environment for middle schoolers (I think that Scratch beats it hands down), so the storytelling component may just have made it a bit better.  Has anyone ever attempted a Storytelling Scratch class? (I wasn’t able to find any equivalent to Storytelling Alice using Scratch in a very brief web search.)

The newest version of Scratch (2.0) runs as a Flash program in the browser, and has some new media-related features (like being able to interact with the video from the computer’s camera).  My son has played with it a bit, but I’ve not had time to explore the new features.  The Flash-based Scratch means that no installation is necessary to run programs, but that Scratch will not run on iOS devices (like iPads), which could be a limitation at many schools.  I understand that an iPAD app or HTML5 implementation of Scratch is planned, now that Scratch 2.0 has been released.

A better approach than stories about science may be to have more hands-on science and engineering, where students learn the science and engineering in order to accomplish something, not just to pass a course and get into college.  So far, most attempts along those lines have favored stereotypically “boy” goals (robot sports, for example, and video games), and so have not served to shrink the gender gap.

2013 March 30

A physics teacher’s reaction to anti-science witch hunts

Filed under: Uncategorized — gasstationwithoutpumps @ 12:06
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Frank Noschese, a physics teacher, has written a rather amusing “letter to parents” on his blog Dear Parents | Action-Reaction, including such gems as

Giggle-inducing Scientific Terminology. Uranus, excited state, naked singularity, panspermia, ram pressure, Trojans, black hole, galactic bulge, hadron, space probe, parsecs, and 21-centimeter emission, to name a few. These are not “dirty words.” They are official scientific terms and we will need to use them in class.

The post as a whole mocks the anti-science attitude of the Dietrich, Idaho parents who protested a 10th grade biology teacher using the word “vagina” in the unit about reproduction. [http://www.washingtontimes.com/news/2013/mar/28/idaho-teacher-under-investigation-way-he-teaches-h/]

I guess that Idaho is racing Kansas to become the most anti-science state in the United States.

2013 March 28

Science Fair coaching session

Filed under: Science fair — gasstationwithoutpumps @ 23:34
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This afternoon the Santa Cruz County Science Fair tried something new: we had a coaching session for the students going to the California State Science Fair.  Of the 40 projects that were being sent on to state, about half were represented at the coaching session.

The first half of the two-hour session was spent as a large group.  Each of the judges who was there (in their new role of coach) introduced themselves briefly, then we went around the room having each student introduce their poster briefly (about 1 minute each).  Then students asked questions about the state competition—about what they could expect, about poster design, about what judges wanted to see, and so forth.  Since I was the only one there who had judged at state, I ended up answering a lot of the questions, but others got in good comments also.

One message that I think we got out this year was that at the state science fair, students tend to use bigger poster boards than is common at the County Science Fair, so that they can put more content on the poster and still use a large enough font to be readable.  (A lot of the posters had tiny fonts suitable only for close reading.)  The construction techniques for two of the larger posters there were shown.  One was just two ordinary science fair tri-fold boards stacked with PVC pipe glued on the back as a stiffener.  It is quite sturdy, but a bit unwieldy even when folded, since it is still 5’–6′ long.  The other was my son’s foam-core board, which is just as big, but folds up small enough to be carried like a suitcase and be checked as luggage (not small enough to be carry-on though.  I’ve provided detailed construction instructions for this design in a previous blog post (though that post shows the previous carrier box, not the new one that fits the board and surrounds it on all 6 sides).

After the group discussion we broke up into one-on-one sessions with the judges circulating around answering questions for whoever had questions for them.  I ended up doing some coaching for two of the students I had judged, plus one who was doing a bioinformatics project.  I also provided less detailed advice to several other students who had questions.  I got a chance to meet some of the students who I had not seen at the county science fair—I think that we have some potential winners at the state fair this year.

Based on the conversations at the coaching session, I think that we’ll see some changes to this year’s projects before state. But even if we don’t, next year’s projects are likely to be stronger, as these students share what they heard with their teachers and fellow students, as well as improving their own projects for next year.

The coaching session worked well enough that I think we should do it again next year—perhaps lengthening it to 2.5 or 3 hours, with the first 30–45 minutes for a group session and the rest of the time for 1-on-1 coaching.  We could also have used another 4 or 5 judges there, so that students with individual questions did not have to wait to get them answered.

2013 March 10

Santa Cruz County Science Fair 2013

I spent Friday evening and all day Saturday judging at the Santa Cruz County Science Fair, which is always fun, but a little tiring.  This year I was the lead judge for the “Energy and Power” category, which had 14 projects in grades 4–5 and 14 in grades 6–8.  There were no high school projects in my category, and they decided to have interviews but not judging for K–3, so I ended up only talking briefly with the K–3 students and did not give them written feedback.  I interviewed 26 or 27 of the students in my category, and provided written feedback for each of them.  That written feedback is the most important part of the fair, and the judges in my category were all very diligent about providing detailed feedback, so most of the kids got 4 or 5 feedback forms.  In some other categories, a lot of the judges left without providing feedback, and a few kids ended up with no feedback forms. (I heard about it from some of the parents, because the administrator had left before the public viewing, and I was clearly identifiable as a judge—I wear a lab coat for judging science fair.)

The “energy and power” category is where all the lemon batteries end up, which makes it a rather sad category for judges.  Every category has a few projects that appear (usually very badly done) year after year. The lemon batteries are almost always terrible projects, with the students following rote directions from the web (in at least two cases this year, incorrectly) and having no understanding what they are doing.  I think that Science Buddies has a lot to answer for! The students seem to think that the power is coming from the fruit (rather than from the dissimilar metals) and that voltage is the same thing as power.

We also got the windmills, solar cells, wave generators, and thermoelectric devices. Those were generally a little bit better done—we actually had a pretty good solar cell project and a pretty good Peltier-device project. Because our fair does not have an engineering category (other than “environmental engineering”), we ended up with a number of the engineering projects as well (hovercrafts, ducted propellers, and the like).

There is a big need to train elementary school teachers (and to a lesser extent middle-school teachers) in science and engineering methods.  And I don’t mean the nonsense they teach about the “scientific method”, which bears almost no resemblance to any process of scientific or engineering work I’ve ever seen.  I mean that they need to know how to measure voltage, current, and resistance, and to be able to show kids how to compute power (it is not the same thing as voltage, nor is it the product of open-circuit voltage and short-circuit current).  Teachers should be able to show students how to build a simple calorimeter and measure energy from chemical reactions (like burning fuel). A lot of the students I interviewed were quite bright, but no one had ever taught them the basics they needed to be able to do their projects.  Nor have they been taught how to use the tools they have. I don’t want to see another student wrapping the loop for measuring AC current around a wire and claiming that they are measuring resistance, nor claims that lemon batteries produced 9 Amps at 1v.

Things I learned when I was 8–10 years old should be within reach of their teachers. I think that a few hours of professional development that involved them actually doing some measurements and learning the basics of some of the science and engineering projects would improve the quality of their students projects a lot. Every elementary school teacher should know how to use a hand saw, a drill, wire strippers, and a soldering iron, and they should be teaching the kids how to use them also.  (Yes, I can see the safety problems if you try to do it in a large class—but the safety problems in PE classes are far larger, but we haven’t thrown out all sports in schools because of it.)

Even just telling the teachers some basic ideas might help.  Some of the things I see repeatedly:

  • Know what you are measuring (voltage is not power).
  • Measure the right thing to answer the underlying question.
  • Measure inputs as well as outputs (counting colonies tells you how many culturable bacteria or fungi were in your initial sample, which is useless if you don’t know how big the sample was).
  • Don’t culture unknown micro-organisms (except in a lab with proper protection and sterilization equipment).
  • Read (and cite) some material from the web. High school students should be going well beyond Wikipedia in their literature searches, but even a short Wikipedia seach would be a big step up for most of the middle school and elementary school students.  If Wikipedia is too difficult for an elementary school student (as it may well be), see if there is anything useful on Simple English Wikipedia.
  • Good science fair projects take time, often with many false starts. There are way too many 1-week projects at the county science fair.
  • Mentorship is good, but doing the work for the kid is not—especially not the interpretation of the results. This point is aimed more at the over-involved parents than the teachers—but judges have to be very careful, as there are some highly motivated kids doing things that look like adult work, but really are just the student.  (I remember an incident about a decade ago, of a kid in another category who was severely down graded by the judges in who thought they were judging a parental project, but I talked with the kid for 15 minutes later on and I was convinced that the work really was his alone.  I was angry at the judges for not being more careful in their judgements, but there was nothing I could do about it.)

It’s great to see the enthusiasm and talent of the K–3 group (which has been growing so rapidly that the hall that is rented for the Science Fair is no longer big enough), but that enthusiasm and talent seems to dissipate rapidly around middle school—there are still a lot good middle-school projects, but there are also a number of kids just going through the motions and only a few are continuing to do science fair once they are not required to.  I see more evidence of parental over-involvement at middle school than at elementary school (though that may be due to the selection processes at the different feeder schools, rather than inherent in the age groups).  I didn’t see any evidence of over-involvement in my category this year—if anything, I saw the opposite, with students not getting critical guidance so that they could do a really meaningful project.

One very sad part of the county science fair is how few high school students participate.  There are no school-level fairs in our county at the high school level, and little or no encouragement of individual projects.  This year I think we had 23 projects from high school students, out of a population of about 7500 high school students—about 0.3%.    According to the statistics from the Bureau of Labor Statistics, the various STEM categories add up to about 6% of the workforce (not counting healthcare, which would double the number, and not counting several related occupations, like high-school science teachers, scientific sales, science and engineering managers, …).  So even with very conservative counting, we’re short by a factor of 20 in this county.  I’d be satisfied if even 1–2% of the high school students were entering science fair, but we’re nowhere close to that number, and the participation at the high-school level is shrinking, not growing, each year.

The problem is not strictly a local one—most places see a drop in participation from middle school to high school, but I don’t think many are as extreme as here.  There are some places in the US where high school science fair is big—what have they done differently?

Lots of organizations have seen the problem of high school students losing interest in science fair, and they have put up cash prizes and other incentives for high school students, but (in this county anyway), no one is taking the bait.  We need to find a way to get high-school students excited about doing science or engineering projects, and I don’t know what would stimulate that excitement.

Many (most?) of the good projects in middle school and high school came from home-schooled kids or kids getting a lot of after-school education from mentors or parents.  This may be related to the point that good science fair projects take time and require passion on the part of the students, and the local schools (public, private, and charter) don’t provide a good environment for projects that take time nor for students to show passion—way too much busywork and time wasted preparing for standardized tests.

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