prisingly, when experienced teachers have intensive prepara-
tion in the physics involved, the quality of student learning is
even better.
V. CONCLUSION
In this paper, we have illustrated howPhysics by Inquiry,
a research-based curriculum developed by our group, can
help preservice and inservice teachers deepen their under-
standing of the topics that they are expected to teach.21,22
Evidence has also been presented of a significant increase in
learning by ninth-grade students who were taught by teach-
ers who had worked through this curriculum.
Because of their influence on large numbers of students,
K-12 teachers should have a strong command of basic phys-
ics and physical science. Results from research conducted
among physics majors and graduate students, all of whom
have taken courses on more advanced material, indicate that
these courses often do not help them deepen their under-
standing of some important concepts taught in high school.^23
Descriptive survey courses are inadequate preparation for
teaching physical science in elementary and middle school.
Moreover, as has been illustrated, experience in teaching a
topic does not necessarily lead to the development of a func-
tional understanding. There is therefore a need for special
physics courses for elementary, middle, and high school
teachers. Some important features of these courses have been
illustrated in this paper and are also discussed in the Guest
Editorial in this issue.^1
ACKNOWLEDGMENTS
The research and curriculum development described in
this paper were a collaborative effort by many past and
present members of the Physics Education Group at the Uni-
versity of Washington. Donna Messina, a former high school
teacher, led the preservice teaching project. Karen Wosilait
collected and analyzed data from her ninth-grade class. Sup-
port from NSF for our annual Summer Institutes for Inser-
vice Teachers and for the development ofPhysics by Inquiry
made these related projects possible.
(^1) For specific references and additional discussion, see L. C. McDermott,
“Preparing K-12 teachers in physics: Insights from history, experience,
and research,” Am. J. Phys. 74 , 758–762 2006 .
(^2) Other important aspects include classroom management, social and cul-
tural problems, psychological concerns, epistemological beliefs, and
theories of learning.
(^3) L. C. McDermott, “A perspective on teacher preparation in physics and
other sciences: The need for special courses for teachers,” Am. J. Phys.
58 , 734–742 1990 ; “Teacher education and the implementation of el-
ementary science curricula,”ibid. 44 , 434–441 1976 ; “Improving high
school physics teacher preparation,” Phys. Teach. 13 , 523–529 1974 ;
“Combined physics course for future elementary and secondary school
teachers,” Am. J. Phys. 42 , 668–676 1974 .
(^4) L. G. Ortiz, P. R. L. Heron, and P. S. Shaffer, “Student understanding of
static equilibrium: Predicting and accounting for balancing,” Am. J. Phys.
573 , 545–553^2005 .
P. S. Shaffer and L. C. McDermott, “A research-based approach to im-
proving student understanding of the vector nature of kinematical con-
cepts,” Am. J. Phys. 73 , 921–931 2005 .
(^6) L. C. McDermott and P. S. Shaffer, “Research as a guide for curriculum
development: An example from introductory electricity, Part I: Investiga-
tion of student understanding,” Am. J. Phys. 60 , 994–1003 1992 ;ibid.
61 ,81E 1993 ; P. S. Shaffer and L. C. McDermott, “Research as a
guide for curriculum development: An example from introductory elec-
tricity, Part II: Design of instructional strategies,”ibid. 60 , 1003–1013
1992 .
(^7) L. C. McDermott, P. S. Shaffer, and M. D. Somers, “Research as a guide
for teaching introductory mechanics: An illustration in the context of the
Atwood’s machine,” Am. J. Phys. 62 , 46–55 1994 .
(^8) K. Wosilait, P. R. L. Heron, P. S. Shaffer, and L. C. McDermott, “Devel-
opment and assessment of a research-based tutorial on light and shadow,”
Am. J. Phys. 66 , 906–913 1999 ; P. R. L. Heron and L. C. McDermott,
“Bridging the gap between teaching and learning in geometrical optics:
9 The role of research,” Opt. Photonics News^9 ^9 , 30–36^1998 .
The results support the views expressed in Ref. 1.
(^10) L. C. McDermott and E. F. Redish, “Resource letter: PER-1: Physics
education research,” Am. J. Phys. 67 , 755–767 1999 .
(^11) See, for example, “Balance and motion,” inFull Option Science System
Lawrence Hall of Science, Berkeley, CA, 1995.
(^12) See “Background for the teacher,” p. 2 of “Balance” in “Teacher Guide:
Balance and motion,” inFull Option Science SystemLawrence Hall of
Science, Berkeley, CA, 1995.
(^13) L. C. McDermott and the Physics Education Group at the University of
Washington,Physics by InquiryWiley, NY, 1996.
(^14) PbIhas been used in courses for nonscience majors, as well as in prepa-
ratory courses for students aspiring to science-related careers but who are
underprepared in science and mathematics. Two examples are R. E.
Scherr, “An implementation ofPhysics by Inquiryin a large-enrollment
class,” Phys. Teach. 41 2 , 113–118 2003 and L. C. McDermott, L. K.
Piternick, and M. L. Rosenquist, “Helping minority students succeed in
science, Part I. Development of a curriculum in physics and biology,” J.
Coll. Sci. Teach. 9 , 136–140 1980 .
(^15) The term “pedagogical content knowledge” was introduced by L. S. Shul-
man, to characterize what a teacher needs to know beyond the content
and pedagogy in order to help students learn. See, for example, L. S.
Shulman, “Those who understand: Knowledge growth in teaching,” Edu-
cational Researcher 15 2 , 4–14 1986 .
(^16) This question is discussed in greater detail in Ref. 7.
(^17) L. C. McDermott, P. S. Shaffer, and the Physics Education Group at the
University of Washington,Tutorials in Introductory PhysicsPrentice
Hall, Upper Saddle River, NJ, 2002.
(^18) See, for example, the discussion of research in the context of electric
circuits described in L. C. McDermott, P. S. Shaffer, and C. P. Constan-
tinou, “Preparing teachers to teach physics and physical science by in-
quiry,” Phys. Educ. 35 6 , 411–416 2000 .
(^19) For a more detailed description of the teaching experience, see D. L.
Messina, L. S. DeWater, and M. R. Stetzer, “Helping preservice teachers
implement and assess research-based instruction in K-12 classrooms,”
AIP Conf. Proc. edited by J. Marx, P. Heron, and S. FranklinAIP,
Melville, New York, 2005,p.97.
(^20) See Secs. 1 and 2 of the moduleLight and ColorinPhysics by Inquiry
21 Ref. 13.
In addition to the examples from dynamics and geometrical optics dis-
cussed in this paper, see also the second paper in Refs. 6 and 18.
(^22) For additional assessments of teacher understanding in courses based on
Physics by Inquirythat were reported by faculty at other institutions, see,
for example, R. E. Scherr, “An implementation ofPhysics by Inquiryin a
large-enrollment class,” Phys. Teach. 41 2 , 113–118 2003 ;K.C.
Trundle, R. K. Atwood, and J. E. Christopher, “Preservice elementary
teachers’ conceptions of moon phases before and after instruction,” J.
Res. Sci. Teach. 39 7 , 633–658 2002 ; J. A. Marshall and J. T. Dor-
ward, “Inquiry experiences as a lecture supplement for preservice el-
ementary teachers and general education students,” Am. J. Phys. 68 7 ,
S27–S36 2000 ; B. Thacker, E. Kim, K. Trefz, and S. M. Lea, “Com-
paring problem solving performance of physics students in inquiry-based
and traditional introductory physics courses,” Am. J. Phys. 62 7 , 627–
633 1994 ; and S. M. Lea, “Adapting a research-based curriculum to
disparate teaching environments,” J. Coll. Sci. Teach. 22 4 , 242–244
1993 .
(^23) See, for example, Refs. 4–6 and 8.
767 Am. J. Phys., Vol. 74, No. 9, September 2006 McDermottet al. 767