Re: [Phys-l] pre-to-post tests as measures of learning/teaching #2

["John Clement" <clement@hal-pc.org>]

> "Many traditional physics instructors think that introductory physics
> courses should focus on the "skill" of *problem solving.* They assign
> vast numbers of back-of-chapter problems and devote lectures and
> "recitations" to going over problem solutions.  Sorry guys, pre/post
> testing demonstrates that "Students do not overcome conceptual
> difficulties after solving 1000 traditional problems" [Kim & Pak
> (2002)]."

The ability to solve problems is enhanced by first getting conceptual
understanding.  This was shown by Eric Mazur.  There is also the paper by
Michelle Perry which shows that teaching algorithms kills the ability to
transfer.  Actually problem solving needs to be attacked separately, in
addition to getting conceptual understanding.

Concentrating on back of the chapter problem solving is analogous to
backwards problem solving.  This is treating an end stage symptom without
looking for the cause.  Students habitually look at the required answer and
try to work backwards to find it.  They don't work forwards by taking the
information and then trying to generate more information.  Working backwards
will not work with rich context problems, but it often works with many of
the simplistic end of chapter problems.

Essentially instructors are working backwards by assigning lots of end of
the chapter problems.  They need to be working forwards by first getting
students to understand the concepts, then by assigning problems where the
concepts must be used to get the solutions.  In this process, the number of
traditional equations needs to be reduced to a minimum, and concepts need to
be used instead of equations wherever possible.  For example the SVT
equations can be pared down dramatically, and the ideas of slope and area
can be used instead of the missing equations.  Also most of the end of the
chapter problems are crappy because they can be worked backwards by just
finding the appropriate equation.

Concentrating on problem solving is like treating diseases symptomatically
only, without looking at the underlying causes.

John M. Clement
Houston, TX

Reference: Cognitive Development, 6, 449-468 (1991)
Learning and Transfer: Instructional
Conditions and Conceptual Change
Michelle Perry
University of Michigan

Abstract: It is widely assumed that instruction plays a role in learning and
in transfer. The present studies examine how type of instruction (containing
principle-based vs. procedure-based information) influences learning and
transfer in a mathematical concept. In the first study, both types of
instruction led a comparable number of children to learn, but
principle-based instruction led significantly more children to transfer
their new knowledge. In the second study, the types of instruction were
combined (i.e., children received both principle and procedure information).
The results were virtually identical to the results obtained from the
procedure-only instructions. This indicates that principle-based instruction
may be crucial for transfer to occur and, when children also are exposed to
procedures, few will transfer. It is hypothesized that children may ignore
the conceptually rich information inherent in the principle when procedures
are also provided.