Three purposes of this study were to: (1) propose some organizing theoretical and observational definitions of the anchor construct; (2) present some initial findings from a diagnostic test designed to uncover anchors for high school physics instruction; and (3) provoke an initial discussion of the new methodological issues that arise in this…

The estimation processes used by fifth through eighth grade students as they responded to computational estimation test items were examined. Interview-based process descriptions were cross-validated using large group test data from an open-ended test and a multiple choice test. Five question formats were used to test different estimation…