At the time, the pretests were administered all instruction
on Newton’s laws in the context of non-rotating objects (typically
modeled as particles) had been completed. In many
cases, instruction on rotational dynamics had also been completed.
Student performance in different lecture sections
taught by different members of the physics faculty was similar
(grouped within a range of 5%), despite the use of different
textbooks or any variations in presentation from section to
section that might be expected. Therefore, we present the percentage
of correct responses averaged over all sections