How effective is modeling instruction?
In
comparison to traditional instruction, under expert modeling instruction high
school students average more than two standard deviations higher on a standard
instrument for assessing conceptual understanding of physics.
The
effectiveness of modeling instruction in enhancing student learning of physics
is being continuously evaluated with well-established standardized instruments.
Chief among these instruments is the Force Concept Inventory (FCI). The FCI assesses the effectiveness of
mechanics courses in meeting a minimal teaching performance standard: to
teach students to reliably discriminate between the applicability of scientific
concepts and naive alternatives in common physical situations. Questions on the FCI were designed to be meaningful to
students without formal training in mechanics.
The FCI has
consistently shown that students bring into their physics courses a wide array
of naive beliefs about the motion of physical objects that are incompatible
with Newtonian theory. Figure 1 summarizes data from a nationwide sample of
7500 high school physics students involved in the Modeling Workshop Project.
The average FCI pretest score is about 26%, slightly above the random guessing
level of 20%, and well below the 60% score which, for empirical reasons, can be
regarded as the threshold for understanding Newtonian mechanics.
Figure
1 shows that traditional high school instruction (lecture, demonstration, and
standard laboratory activities) has little impact on student beliefs, with an
average FCI posttest score of about 42%, still much below the Newtonian
threshold[1]
[2].
This failure of traditional instruction is largely independent of the
instructor’s knowledge, experience and teaching style.
High
school teachers in the Leadership Modeling Workshop Project (1995-1999) began a
shift from traditional instruction to modeling instruction in their first
four-week summer workshop. After their first year of teaching, posttest scores
for students of these novice modelers were about 10 percentage points higher, as shown in Fig. 1
for 3394 students of 66 teachers (large effect size: 0.9). Students of expert
modelers do much better.
For 11 teachers identified as expert modelers after two years in the Project,
posttest scores of their 647 students averaged 69%. Thus student gains in
understanding under expert
modeling instruction are more than doubled (40 percentage points gained),
compared to traditional instruction (16 percentage points gained) (Figure 1).
Subsequent
data have confirmed all these results for a total of more than 20,000 students.
Furthermore, student FCI gains for Arizona teachers, 80% of whom were not physics majors, are almost as high as
those for leading teachers nationwide. Teachers who implement the Modeling
Method most fully have the highest student posttest FCI mean scores.