July 31, 2008

Inquiry Physics

I was looking for something in my storeroom earlier today and stumbled upon my old College Physics textbook. Seven hundred pages of pure applied brutality that every science and engineering student had to complete.

Physics I was the course that sent a large portion of my freshman college class for greener pastures over at the business school. This happened despite the fact that almost every student had taken a high school physics course, so this was the second time through this material.

If my recollection serves me correctly, Physics instruction was supposed to go something like this. The student was supposed to read one or more sections of the textbook every week and attend a lecture given by the professor elucidating the sections we were to have read. A few dozen problems from those sections were assigned to us to work out. Then we attended three hours of recitation classes given by graduate students who worked through some of the problems we had been assigned to make sure we understood what was going on.

This brutal pace kept up for fourteen weeks and we covered nearly the entire textbook. During that time, we worked through hundreds and hundreds of problems. We were permitted to take into each exam one sheet of paper with whatever we could fit thereon. Otherwise, the exams were closed book. Nonetheless, the average grade for each exam was almost always less than 50%.

Here's my question.

How could one possibly teach an inquiry-based (problem-based learning) Physics course and possibly hope to get through more than say a quarter of the syllabus of a lecture-based course? I don't even see how this might work for a high school level course.

Update: Based on Stephen Downes' comment, I sense some confusion. I consider this to be a direct instruction/lecture based course not an inquiry based course. The pace is brutal for a lecture based course. I can't imagine covering this amount of content in a true inquiry based course.

23 comments:

Downes said...

This is a brutal pace? Wow - that explains so much.

It sounds like you had:
- 1 hour of lecture, and
- three hours of tutorial ("recitation")
per week.

Plus: reading of one or more sections, plus a few dozen problems.

Guess what?

That's *standard* for a course in the sciences. I took university courses in chemistry, physics, engineering, computer science, geography and mathematics. *All* of them involved a workload something like that.

Some of the courses - most of them, actually - also included a lab component. On top of the coursework already described.

You ask, "How could one possibly teach an inquiry-based (problem-based learning) Physics course and possibly hope to get through more than say a quarter of the syllabus of a lecture-based course?"

You couldn't. But if you were covering the same material with *just* lectures, far far more than 50 percent of the class would fail.

Because if you don't do the problems during the course, you can't hope to master them on the test. And if you can't master them on the test, then pretty clearly you haven't learned the subject.

There's no short cut. I can't emphasize this enough. Learning physics - or any scientific discipline - is hard. Because you have to do much more than just memorize a few facts, you have to learn to think like a physicist, to see the world in a certain way. Which takes actually doing the work.

Maybe they don't teach that in business school. That would explain, probably, why so many business and economics majors think they are experts in science and technology, making pronouncements on whether something is 'causal' or this and that - when so obviously they know the words but don't understand the practice.

Roger Sweeny said...

How much did the course cover?

Was it just mechanics? (kinematics, forces, momentum, work and energy, torque, pressure and buoyancy, maybe heat)

Or was it mechanics plus electricity and magnetism?

Or mechanics plus electricity and magnetism plus relativity and quantum?

The latter would be ridiculous to try to do in 14 weeks.

The middle would be tough but doable in two 14-week courses. It is what the AP Physics course is supposed to cover (though the AP course pretty much doesn't use calculus).

Just mechanics would make a doable but challenging full-semester course, the more challenging the morel depth you went into and the more you used calculus.

KDeRosa said...

Stephen, I didn't mean to imply that it was anything but a standard course. I'm sure it was. And it was a brutal pace all the same.

With the exception of chemstry, our labs were separate courses that we took after we had been introduced to the underlying material.

But if you were covering the same material with *just* lectures, far far more than 50 percent of the class would fail.

I do not consider this recitation/tutorial to be problem based or inquiry based learning. We were first taught (or learned on our own) the underlying material/formula, and shown some worked problems as examples, then we were asked to work similar problems. We had been taught all the information we needed upfront and then we engaged in hours of practice afterwards. So might call this drill and kill.

ANd, the labs were highly scripted affairs even at the unegraduate level.

I can't emphasize this enough. Learning physics - or any scientific discipline - is hard. Because you have to do much more than just memorize a few facts, you have to learn to think like a physicist, to see the world in a certain way. Which takes actually doing the work.

Yes, what we were doing was acquiring domain knowledge and lots of practice in an attempt to get our understanding from an inflexible level to a flexible level.

What we were not doing was trying to recreate phsyics experiments and derive our own theories/formulas like a physicist. We weren't thnking or acting like physicists, we were acting and thinking like physics students.

That's the crucial distinction you seem to be missing. Or, perhaps, if this is what you think inquiry-learning really is then I think you merely have your terminology confused.

That would explain, probably, why so many business and economics majors think they are experts in science and technology, making pronouncements on whether something is 'causal' or this and that - when so obviously they know the words but don't understand the practice.

Such as when they rely on "correlations" and what not or point to "complexities" to explain away their neeed for better data.

KDeRosa said...

We covered mechanics plus electricity and magnetism and everything in between.

It was a lot of material to cover, especially since you were concurrently taking the calculus sequence, the chemistry sequence, computer programming, and a writing course.

Tom Hoffman said...

If "This happened despite the fact that almost every student had taken a high school physics course, so this was the second time through this material." then how were you and your peers taught Physics in high school and why do you think it did not prepare you for this?

KDeRosa said...

From my recollection:

1. The college text went into considerably more depth than our high school text.

2. The pace was much faster. In high school, we didn't get much past mechanics and energy.

3. The problems we had to solve were more difficult.

4. More than mere regurgitation of familar problems were required on exams.

5. You were expected to teach yourself most of the content from the textbook, with some help from the instructors, as opposed to having all the content taught by the teacher. Less scaffolding.

It was a question of encountering many more problems at a fast pace than what you had previously seen or worked. Which is to say, there was a lot to learn.

KDeRosa said...

Both courses wer taught almost exactly the same, but the college level course has much more rigor. It was designed to weed out the weak and it did so quite effectively.

palisadesk said...

I can't speak to physics (h.s. physics was enough for me, though I have re-discovered it as an area of interest after reading the many works of R. P. Feynman). However, problem-based learning is very successfully used at the professional school level, particularly in medicine. Starting with McMaster University med school in the '60's, which introduced the first completely PBL medical school curriculum (eliminating most lectures, specific courses in anatomy, pathology etc.), a number of medical schools (Southern Illinois University is one) have introduced PBL-based programs, due largely to the results: graduates scored significantly higher on the various licensing and competency exams, and got much higher performance ratings during their internships and residency periods.

Some background info:
History of McMaster medical program development

McMaster site:
McMaster medical school

scholarly article:
Problem-based learning in American medical education: an overview

view from inside the profession today:
Europe
USA

Of course this is a whole different matter than "problem based learning" with children (where it still has a place, but not as a replacement for direct teaching of needed skills and knowledge). However, for some applications, PBL is clearly an effective way to develop the needed competencies. One should note, however, that medical students have already developed a wide range of knowledge, skills and work habits and the PBL challenge is likely effective and appropriate for that reason (among others).

KDeRosa said...

One should note, however, that medical students have already developed a wide range of knowledge, skills and work habits and the PBL challenge is likely effective and appropriate for that reason (among others

Exactly. A point I make al the time. Your ability to implement a real PBL curricula is highly dependent on the students' domain knowledge.

Many law school courses are at least quasi PBL.

TangoMan said...

Let's face the "Inconvenient Truth" here and that is that most teachers aren't smart enough to actually lead inquiry-based teaching effectively enough to produce substantive, and measurable, results in their pupils. At least with lecture-based pedagogy they can rely on teacher's notes but inquiry-based teaching, if it is to be done effectively, requires that the teacher have domain mastery.

To get a sense of what I mean take a look at this essay by Rick Garlikov in which he details his approach to using Socratic Method for teaching Binary Math to 3rd Graders. If he knew jack-squat about binary math then he would be unable to lead the dialog, shape the questions, foresee the logical pitfalls and guide the students away from them, etc. However, because he has complete mastery of binary math he is able to think on his feet and shape his questions in response to the dialog of the moment - he doesn't have to rely on published teacher notes that accompany the textbook, he doesn't have to rely on a lesson plan with most of the points laid out in detail.

Inquiry based pedagogy is more a sop to the teacher's ego, so that the teacher can feel that they're the instrument responsible for the flowering of their students' intellects, than it is about the most effective way to convey knowledge to their students.

I'd love to see a year long cage match between an inquiry advocate, like Tom Hoffman or Chris Lehmann against a Jaime Escalante or a DI teacher who use proven methods and require content mastery before ratcheting up to new concepts.

I don't get the sense that Garlikov would be an advocate of process over content for he clearly has mastery of content. Now, I admit that his experience is quite dramatic but I think that most teachers, especially the ones who have to rely on published teacher notes, are dreaming if they think that they can replicate such processes and deliver to their students the same level of comprehension as was achieved by Garlikov.

KDeRosa said...

Notice the high rate of student responses and engagement which is the goal of any good instruction.

I would think that successfully teaching that way requires quite a bit of skill just like teching lower performing students.

KDeRosa said...

The other thing that makes college physics more difficult is that calculus is prerequisite, unlike high school physics. Does AP physics require calculus?

In any event, my college physics text was General Physics by Giancoli.

Tom Hoffman said...

Neither Chris or I would argue that a good math teacher with a good Algebra I text can't teach kids Algebra I with traditional methods. But there are other ways of looking at math, teaching math, other subjects, other philosophies about what education and schooling is for and about. There are great traditional teachers and great progressive teachers, although the great progressive ones probably don't act the way you imagine they do.

These are complicated issues which, once you get to high school, are rarely tractable to simple analysis of test scores. There is more than one way to skin this cat.

Also, direct instruction is hardly unknown in American high schools. All the studies I've seen indicate that it has always been dominant. I'm sure not executed quite to your satisfaction, but if you believe that American high schools stink, it isn't because they have been taken over by progressive education -- unless you have some data I don't proving otherwise.

Also, for an example of a school that very successfully uses an inquiry-based science curriculum to prepare students for top schools, check out the Illinois Math and Science Academy.

Anonymous said...

tom,

What do you mean by "direct instruction is hardly unknown in American high schools. All the studies I've seen indicate that it has always been dominant"?

If you mean Direct Instruction, then I would disagree. DI is hardly known in K-6 circles, where there is the most impact.

And in terms of "direct instruction", what does that mean? I guess it means "not-inquiry based". But I don't think it means effective. The NMAP report clearly points to deficiencies in math instruction related to bloated curriculum, studying things that don't matter, visiting topics and then dropping them before mastery.

I don't have evidence for this, but my personal experience is that high school math is horribly organized and very difficult for poorly-prepared students to excel.

For example, I remember my high school physics teacher spending *weeks* drawing interference patterns, when we could have done so much more with that time.

And don't get me started on high school geometry. Yuck!

And this was at a public school that was considered to be quite good!

Tracy W said...

However, problem-based learning is very successfully used at the professional school level, particularly in medicine.

I'm probably just showing my ignorance here. But, in medicine, I get the impression that there's an awful lot of stuff that's been learned by empirical work over the centuries (eg different forms of diseases have been identified). How is this taught in pbl-schools?

Dr. P. said...

Physics is one area where education research has paid real dividends. A key is to understand where students are encumbered by pre-existing and often deeply ingrained misconceptions. (see for example “Teaching Introductory Physics” by Arons) and to have enough content knowledge and teaching savvy to recognize and correct these types of student errors.

At the high school level, however, many teachers lack the content knowledge (They don't always recognize this, but one need only look at what states set for their cut scores on the Praxis II test of physics content knowledge to see this. Anyone with a good high school level course should be able to answer 80% of the questions. Yet most states require only 30% or so and very few require more than 50% for a teacher to be “highly-qualified”) and so if you come into your high school class with misconceptions you are likely to leave with them -- even if you get good grades and answer most high school level questions correctly.

At the college level most professors were unaware of these conceptual difficulties. They had no personal experience with them and its easier to think that the students are stupid then that your teaching could be improved.

But well-designed studies (they were designed by physicists afterall) have shown rather conclusively that teaching via “interactive engagement” is very effective at improving students conceptual understanding of physics (google “Force Concept Inventory” for more info)

I had the great good fortune to have had an excellent freshman physics teacher (Milton Stecher -- may he rest in peace)and was able to use the socratic methods (similar to interactive engagment) he so aptly utilized, when I went on to graduate school in physics and was thrust into a teaching role as a T.A.

For six semesters I taught two of about 16 recitation sections for a large intro physics course for engineering students. My students consistently did 5 to 10 points better than the other sections, not because they were smarter, but because they had a better instructor (if I do say so myself)

Anonymous said...

At one of the top Montgomery County (MD) high schools, the AP Physics course taken by two of my children was calculus-based (concurrent AP Calculus BC required), met for 2 periods every day for the entire year, and was preceded by successful completion of Honors Physics. Since there were 3 sections of Honors and only one of AP, the top 36 students who wanted AP were enrolled. 85% of the students received at least a 4 on the AP exam and I think about 1/3 of them received a 5.

AP Chemistry and AP Biology were structured the same, except for the calculus requirement.Some would call that elitest etc. but it was an outstanding program for very talented and dedicated students.

palisadesk said...

But, in medicine, I get the impression that there's an awful lot of stuff that's been learned by empirical work over the centuries (eg different forms of diseases have been identified). How is this taught in pbl-schools?

In fact, the PBL medical program covers the needed material much more quickly (and apparently, based on competency testing of graduates, more thoroughly) than the traditional lecture and assignment-based program. Students complete the McMaster program in just under 3 years, as opposed to the 4 years in most traditional med schools.

For the "how" they do it, my information is mostly anecdotal. I have two good friends who are physicians. They don't know each other, but they have several significant points of similarity: both spent over a decade in other fields and were well established in their careers before deciding to go to medical school in their 30's. One went to McMaster, the other to a traditional-type medical school in Texas (I don't remember which one). Inevitably, since they are friends of mine, we spend time discussing education issues; both have shared their medical training with me in some detail.

As I understand it, the McMaster program is anchored in patient care from Day 1. Students do not attend many classes or lectures (in fact I am not sure there are any!); rather, they are assigned to a small group (6-8 IIRC) which meets and works together throughout the year -- maybe all 3 years (McMaster has a very low attrition rate, due perhaps to their extremely selective admissions and their preference for mature students -- late 20's to mid 40's -- who have already had successful work and life experience in other fields).

The group reports to the hospital and is assigned to a specific area -- pediatrics, pathology, whatever -- and makes rounds with staff, learns about individual cases, etc. What sequence of skills they are required to acquire I don't know, but the group is closely mentored, they are expected to work and study together (there is plenty of assigned reading and research, but virtually all related to their hospital placement and cases). They have many assignments, individual and collective, they learn practical skills like inserting IV's and taking histories early on, are expected to learn how to independently search medical databases for the most up-to-date information on relevant topics (dialysis, specific pharmaceuticals, whatever).

According to the research I read about it (as well as my friend's experience), the program develops a widely competent practitioner who is a skilled independent learner -- vitally important in a field as quickly changing as medicine -- and a lot of interpersonal skills, ability to communicate and negotiate, etc --also urgent today where the "Lone Ranger" physician is an anomaly. The fact that most of the learning is attached to real cases and situations probably makes the vast amount of factual material medical students must absorb better integrated and accessible, since it is in context and related to multiple factors.

In addition to their group hospital work, students also had placements in private clinics or practices, again from very early on (whereas some traditional programs do not provide a lot of practicum experience in the first 2 years). Another advantage, from the student's point of view, is that the intense immersion in a variety of settings makes it easier to identify what specialty or line of practice s/he is best suited for. Many "Mac" graduates have gone on to international prominence in their chosen specialties.

My friend who attended a traditional program also did very well, but the lack of practical experience delayed her ultimate specialization. She initially went into surgery (it was quite competitive getting into a residency in that specialty) and it took a year for her to realize that this was not what she really wanted to do, despite her success. She managed to change programs but I believe this delayed her training for one more year. Ultimately she qualified as a clinical pathologist and headed the department in a hospital out west.

Both systems obviously produce qualified and capable doctors. However, the PBL system does seem uniquely suited to a certain demographic: highly competent, independent, mature and self-disciplined people who want to be engaged in the "real world" applications of what they are learning from the get-go (and have the needed background and personal characteristics to do so). I've never wanted to be a doctor (hate the sight of blood!) but if I did, the McMaster approach would suit me far better than the traditional one. These students are expected to "take responsibility for their own learning" but for once, that is an appropriate expectation -- whereas for Kindergarten children it is ridiculous.

There are students as early as middle-school age (and perhaps earlier) who are highly motivated, need only guidance and "facilitating" to soar ahead, and PBL is probably appropriate for these kids too, although some subjects, such as mathematics and foreign languages, are best taught with a mixture of didactic and experiential approaches.

palisadesk said...

Further to Tracy W's point about empirical work -- it appears that McMaster was also a pioneer in the development of the emphasis on "evidence-based medicine" (EBM) I remember reading about it and found some background information here:
see history of EBM

This was a term new to me until 2 years ago. I've always had an interest in criminal law (strictly as a spectator sport) but when a very interesting and controversial local case went to the Court of Appeal I took advantage of the opportunity to attend and watch some of the testimony from the public gallery. One expert witness, called by the defense, was an extremely knowledgeable and articulate forensic pathologist, who detailed at length what "evidence- medicine" was and how its principles applied to this case (he had also been asked to re-examine the forensic evidence in the case, and had highly credible testimony about it).

I could see immediately a parallel, in cognitive terms, to practices in education -- which urgently needs to become more "evidence-based" -- and to clinical psychology, which has already moved in that direction. As other fields embrace evidence-based practices, there could be more pressure on education to follow suit -- but I am not sanguine about this possibility.

The pathologist, and other expert witnesses, apparently convinced the Court of Appeal, which overturned the lower court verdict, based largely on the forensic evidence which indicated no link between the accused and the actual crime, and the probability of time of death of the victim, as established by EBM protocols, in fact excluded the accused as the perpetrator. The judgment was a masterpiece of clear and cogent writing -- something I have noticed in legal judgments I've had occasion to read. Don't know if that is typical, but somewhere along the line lawyers -- or judges -- learned to write well.

Anonymous said...

Physics, like math and history, should not be taught in a single year, anyway. How could anyone possibly learn physics -- inductively, as they should; not by memorizing a bunch of formulas, mathematics, and ideas thrown at you -- in a year?

Physics is an important subject: it tells us about the world in which we live, breathe, act, think, and value.

It should be taught over a multi-year period.

--Michael Gold
Houston, TX

Anonymous said...

Michael (and others)

Teaching inductively is extremely time inefficient.

It's MUCH more efficient to teach all of those formulas you eschew and get kids to master their use.

Understanding will follow as they become more proficient and have more experience.

Look at Direct Instruction. It is clearly the most efficient teaching method available, and it focuses on teaching skills. Trust me . . . the kids who go through a full DI experience, end up with terrific understanding . . . and deep skills

Roger Sweeny said...

The other thing that makes college physics more difficult is that calculus is prerequisite, unlike high school physics. Does AP physics require calculus?

There are two AP Physics courses. Physics B has almost no calculus. However, most high school AP physics B students are taking calculus at the same time. Which means that somewhere in the first half of the year, they will learn that velocity is the first derivative of position with relation to time, and acceleration is the second.

On the other hand, a statement like, "momentum is the time integral of force" will leave them scratching their heads.

Calculus C does use calculus and requires that students either take concurrently or have already taken calculus. The Physics C web page says, "The following textbooks are commonly used in colleges and typify the level of the C course. ... Giancoli, Douglas C. 2000. Physics for Scientists and Engineers, 3rd ed."

Roger Sweeny said...

The last paragraph above should begin, "Physics C."