Jumat, 18 Juni 2010

The future of AP Physics B

You may have heard rumblings about the AP Physics B redesign.  In sum, the College Board got a huge windfall of government grant money to examine the effectiveness of the algebra-based AP course.  And, in part since it's unwise to accept millions of dollars and then say "thanks, but we're all good," the Physics B course will change.  In several years (no clue exactly how many), Physics B will become two courses:  Physics B1 and Physics B2.

There are two major reasons for the change.  The stupid reason is based on an early 2000s report from a committee of physics professors blasting the AP B course for its predominance of mathematical manipulation and lack of physics reasoning skills.  Problem is, they were looking at outdated exam questions.  Since 1996 or so, the Physics B exam questions have been rather powerful evaluators of reasoning skills.  The negavitve conclusions of that committee about AP physics B were based on incorrect assumptions; thus, the huge grant and the redesign.

The GOOD reason for the redesign is the overly extensive breadth of the Physics B curriculum.  Sure, some teachers get through all of the necessary topics.  Sure, many of us also believe that a broad survey course is the correct way to begin a high school student's physics education.  However, the vast majority of teachers can not get through the full B course.

Consider two students who earn a 3 on the current AP physics B exam... student 1 has a half-arsed understanding of all of the numerous topic areas, and so earns about 1/3-1/2 credit on all of the free response questions due to his shallow partial credit responses.  Student 2 has NOT covered all the material on the exam, but has a serious grasp of what he has covered.  Student 2 might earn most all of the points on several free response questions while leaving the others blank.

Colleges want to differentiate between students 1 and 2.  Student 2 has a potential future as a physics major, and thus is a candidate for a limited amount of advanced placement; even if he doesn't continue on in physics, he has demonstrated a depth of understanding that is at the college level and thus worthy of some college credit.  Student 1, though, can not talk intelligently about physics.  College professors want to reward student 2 (with admission, credit, and placement) but not student 1.

So, B1 will be *easily* short enough to teach in one year, as will B2.  However, the combination of B1 and B2 will probably be too much to be taught as a single first-year course.  That is the goal.

As for the content of each course:  In July, the curriculum development committee is scheduled to release the topics and curriculum goals for B1 and B2.  It's not as simple as splitting Physics B down the middle, because of state standards, or at least state standards in large, influential states.  For example, the New York Regents exam covers simple circuits.  If AP B1 did not include circuits, then presumably New York schools would be hesitant to teach B1 as a first year course.  The committee has navigated all kinds of political minefields in deciding upon its final course content.*

* Which, therefore, will likely draw complaints from EVERYONE.

More importantly, the committee is committed to testing conceptual understanding throughout the test.  The style of questions will be changed such that verbal justification is not an afterthought to a calculation, but rather is the primary focus of each problem.  For example, consider this year's AP physics B2, about a fluid mechanics experiment similar to one I do in class.  The test asked for a derivation, followed by graphical analysis and interpretation of experimental data.  A source close to the committee suggested that the style of the redesigned exam questions would likely BEGIN with the experimental data, verbal analysis and interpretation... and only then require derivation and calculation.

What should you, personally, do about this?  Well, nothing, for now.  The Physics B test will not change for a few more years.  Over the next few years, you might consider how a B1 and B2 course might fit into your overall curriculum.  I'm myself considering teaching B1 as our honors freshman course; then, B2 would be a junior-senior course in the style of my current B course, but open only to those who have passed the B1 exam.  Others are considering dropping Physics B and teaching Physics C as a second year course, or C mechanics as a first-year.  Most who already teach an honors first-year course will just combine B1 and B2 into a single, second year course.

And finally, do consider ramping up your emphasis on written justification and conceptual understanding.  Sure, my students will always memorize equations.  But your calculus student with the 750 math SAT who is obstinate about not showing his work will not survive in Physics B1 and B2.  If you're not already doing so, step up the fight against the student who thinks physics is all about calculating the right answer.  That's what good physics teaching is, anyway; and that's the style of teaching that will promote success on the redesigned exams.

GCJ


Tidak ada komentar:

Posting Komentar