P. R. L. Heron, and P. S. Shaffer, Investigating student
understanding of static equilibrium and accounting for
balancing,Am. J. Phys. 73 , 545 (2005).
[39] See the state science content standards (Ref. [28]), content
standard 1a for grade 5, p. 14.
[40] A paired-samplesttest showed a statistically significant
gain in the mean percent accuracy on the total PCA
and for each stimuli format (t¼ 10 : 45 , df¼ 211 ,
p 0 : 05 ).
[41] See state standards, Ref. [8]. The energy questions are
covered by grade 9-12 physics standards 2a-c, p. 32. Heat
and temperature are covered by grade 6 standard 3, p. 19.
Particulate models of matter are included as early as
grade standard 1a, p. 8, with particulate models of differ-
ent states of matter appearing in grade 8 standard 3d-e,
p. 27.
[42] This problem and related data are also shown in
M. Loverude, Student understanding of gravitational
potential energy and the motion of bodies in a gravita-
tional field, Physics Education Research Conference,
AIP Conf. Proc. No. 790 (AIP, New York, 2004),
pp. 77–80.LOVERUDE, GONZALEZ, AND NANES PHYS. REV. ST PHYS. EDUC. RES.7,010106 (2011)
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