PhysTEC Teacher Advisory Group Meeting 4/24/2007

Summary of Discussion led by Joe Redish:

notes by R. Tanner (and N. Finkelstein)

TAG – April 24, 2007

Present (20 total):
Practicing Teachers: Brad Boyle, Karen King, Michael Fuchs, Andy Leonard, Cory Hofschild, Helen Petach, Roberta Tanner
Students: Gabe Thatcher, Emily Quinty, Ward Handley, Aaron (LA for APPM – did not get last name), Portia Wolf, Shrishti Yadav.
Staff and Graduate Students: Chandra Turpen, Valerie Otero, Noah Finkelstein, Michael Dubson, Steven Pollock, Kathy Perkins, Joe Redish.

Joe Redish Discussion
Joe Redish led a discussion starting with “Besides the content, what do you really want your students to learn? Of course there is the vocabulary, the equations, and so on, but there must be more.” The discussion is summarized below.

Quantifying Everyday Life:
Joe wants students to be able to quantify their everyday experiences, and not just in physics. He uses estimation problems, but ones more easily calculated than Fermi’s problems (Fermi asked things like “how many red-headed piano tuners are there in NY city”). Joe might ask students to estimate the number of people the football stadium can hold, or how many novels could you put on an 800 Megabyte CD if 1 character is 1 byte. Joe puts an estimation problem on each homework and on each exam.

Andy told us about a summer class he teaches for the best and brightest, about oil and geology. The summer class is a week-long experience in which students visit oil wells, look at bore-hole and other data, and draw conclusions about where to find oil. He contrasted that with what we often do in the classroom where we teach lots of little pieces and hope that we put it together for students or that they put it together for themselves.

We summarized Andy’s ideas a making connections to the world, connections to student’s lives, and connections to other things they are learning. A context with powerful and worldwide societal implications makes learning personally meaningful.

Joe does this on a smaller grain size, for example, asking students if it is easiest to open a door by pushing it in the middle or edge?

Skepticism and Evidence:
Mike F listed improving communication and organizational skills, being scientifically skeptical, and demanding evidence. Joe summarized the latter ass epistemology: how do we know stuff?

One example expressed was to measure “g” on different planets in Star Wars. Various things fall on different planets. Logger Pro or a similar computer program can be used to graph points and “g” can be determined.

Scientific Literacy:
Karen mentioned that students need to understand what they are seeing. We spent quite some time listing what scientific literacy really means.
One example was for students to understand the energy debate. For example, where does the energy come from if you drive a hydrogen car? Joe said we might also talk about the “entropy” debate.
Included in scientific literacy are vocabulary, numeracy, observation and inference, statistics, multiple representations including graphs, diagrams, equations, words, and understanding relationships (coherence) between values like position, velocity, and acceleration. Sometimes students can tell you how to calculate or graph one of the above from the other, but they do not understand the how these quantities are related. One example illustrating students’ problems with numeracy is a concept test asking what 1E5 means. Is it 1 x 105? 105? 106? etc.

Another idea under scientific literacy included understanding the difference between laws, definitions, and special case formulas. Mike D mentioned that there are lots and lots of formulas in the textbook and most of them are wrong (the special case formulas are not correct except under specific conditions). Students must be able to discern the few laws and definitions from which all the other formulas are derived.

Students should also be able to differentiate between journalism vs. scientific documents, and learn how to talk in an acceptable way in a scientific discussion (i.e. “the evidence shows” instead of “I feel”).

Problem Solving:
The last area of importance was that students should learn to solve problems using a variety of approaches. They need to be able to select or develop the correct equations or solution principles, evaluate whether their answers, (or even their solution path), is correct, and know how to get “unstuck” or to proceed when they reach a dead-end in their problem solving approach. Students should learn how to solve problems by articulating with groups, and how to build models from evidence.

Joe finished by explaining examples of difficult problems he gives his students. He tells his students that each problem should take about an hour to solve.

If the federal deficit is $5 billion, and you got that in $1.00 bills, how much of [Colorado] would that cover? What is the per person deficit? Is [some number] reported by a politician valid?

In the problem with two masses linked by a string over a pulley, one mass is hanging and the other is on a ramp (pulley at top of the ramp) he might ask students what approximations they would make so they could do the problem in a reasonable amount of time? (at least 5). Which approximations would you eliminate first to get an answer closer to the real situation?

Someone else said they ask graduate students “How often does a bee have to flap its wings” and the first question they ask is “What approximations can we use?” The answer is “It’s a real bee”!

Model Building:
Teaching students go about how to build scientific models. The PET curriculum is designed to do this (see more about this on the “announcements” page).