Teacher Education in Physics

Summary: McDermott, et al.

matter, to understand not only what we know but also on what

evidence and through which lines of reasoning we have come

to this knowledge.

Although our decision to create a combined course for

several populations was initially motivated to increase enroll-

ment, other advantages became apparent. All of the prospec-

tive teachers benefi ted from the unusual class composition.

The elementary school teachers developed skill in propor-

tional reasoning and in ability to apply simple geometry,

trigonometry, and even vector algebra. Teachers at all levels

demonstrated substantial growth in logical reasoning and in

the use and interpretation of graphical representations. After

a year of learning by inquiry, the elementary school teach-

ers had acquired suffi cient self-confi dence to help wean their

secondary school classmates from dependence on memorized

formulas and textbooks. The elementary school teachers

quickly became aware of their own greater skill in inquiry-ori-

ented learning and were not intimidated about asking for help.

They were willing to accept, however, only a certain type of

assistance. Some would say “Don’t just tell me the answer, I

want help in fi nding out for myself.” Such statements helped

the high school teachers recognize the value of independent

learning and encouraged them to refl ect on their own intel-

lectual development.

II. EVOLUTION OF UW PHYSICS COURSES FOR

K-12 TEACHERS (1974-2006)

In the 1990s, the student population in the combined course

gradually changed. It began to include physics graduate stu-

dents with a strong interest in teaching. The preservice course

for elementary school teachers was discontinued. Thus there

were no graduates of that course to take the combined course.

We continued to offer the NSF Inservice Summer Institutes

for teachers from elementary through high school, as well

as an academic-year Continuation Course open to all former

participants in any of our courses for teachers.

The present version of Physics by Inquiry (PbI) is the result

of a long iterative process. Not intended to be read like a text,

PbI consists of laboratory-based modules that contain care-

fully structured experiments, exercises, and questions that

require active intellectual involvement. The equipment is

simple and can be reproduced in K-12 classrooms. The stu-

dents collaborate in small groups as they work through the

PbI modules. Experiments and exercises provide the basis on

which they construct physical concepts and develop scientifi c

reasoning and representational skills. The role of the instruc-

tor is not to present information and answer questions but to

engage students in dialogues that help them fi nd their own

answers. Expressly designed for use with teachers, PbI has

also worked well with other populations.

PbI provides the opportunity to learn (or re-learn) physics

in a way consistent with how teachers are expected to teach. It

is characterized by four general principles:

• Concepts, reasoning ability, and representational skills
  are developed together within a coherent body of subject
  matter.


• Physics is taught as a process of inquiry, not as an inert
  body of information.


• The ability to make connections between the formalism of
  physics and real world phenomena is expressly developed.
  
  
  • Certain common conceptual and reasoning dif fi culties that
    students encounter in physics are expressly addressed.
  
  
  
  

Implementation in PbI of the fourth principle required sys-

tematic research to determine not only what students could or

could not do but also whether the instructional strategies we

developed were effective. Daily interactions with individual

students in the combined course suggested that systematic

questioning would be fruitful for probing student thinking

in depth. During the early days of the combined course, we

also began trying to identify the conceptual and reasoning

diffi culties that physics presents to underprepared students

who aspire to careers in science, mathematics, and medicine.

In 1973, the year before the paper on the combined physics

course was published, our group began exploring student

understanding in physics by conducting individual demon-

stration interviews.^5 The students involved were enrolled in

the courses for K-12 teachers, special courses with similar

content that we offered for under-prepared students, and the

standard large introductory physics courses. In 1980–1981

the American Journal of Physics published two papers that

reported on some of this early research.^6

During the 1990s we began to administer pretests and post-

tests to large numbers of students from the introductory to the

graduate level. We identifi ed many similar intellectual hurdles

with basic physics in all of these populations and often found

that similar instructional strategies worked well. Teachers

who might not have a particular diffi culty themselves would

certainly have students who did. Therefore, a well-prepared

teacher of physics or physical science should have acquired,

in addition to a strong command of the subject matter, both

knowledge of the challenges that it presents to students and

familiarity with instructional strategies most likely to be

effective. As the combined course evolved and as the devel-

opment of PbI progressed, the prospective teachers in our

classes gained this experience.

III. NEED FOR SPECIAL PHYSICS COURSES FOR

K-12 TEACHERS GUIDED BY PHYSICS EDUCATION

RESEARCH

The other two papers on teacher preparation reprinted here

were published in 1990 and 2006, respectively, long after

the paper on the combined course. Together they describe

the need for in-depth preparation of teachers in physics and

comment on how we determine through research whether the

instructional strategies that we develop are effective.

The 1990 paper begins by summarizing the history of K-12

science education in the U.S. and describes the ongoing lack

of appropriate preparation for teachers at all levels of instruc-

tion. A strong case is made for physics departments to offer

special courses for both preservice and inservice teachers.

The 2006 paper supports these recommendations by illustrat-

ing the mismatch between standard topics in the K-12 cur-

riculum and the physics knowledge of many teachers. The

following examples are in the context of balancing, kinemat-

ics (acceleration), electric circuits, dynamics, and geometri-

cal optics.

Elementary school curricula often include a unit on bal-

ancing. About 50 elementary school teachers (many of

whom had taught this topic) were shown a diagram of a

baseball bat balanced on a fi nger placed closer to the wide

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