Problem categorization.—Items in this test are similar to
the 3-problem categorization tasks used in Ref. [25] but
modified to be grade appropriate. Students must select one
of two problems that would be solved most like a third
“model” problem. Problems are specifically designed to
vary their match on superficial features (objects or context)
or match on concepts and principles used to solve them.
This test evaluated ability to determine if problems were
solved with similar principles and whether students were
distracted by the presence of similar surface attributes in
problems. Total time: 25 min for 9 items.