The Impact of Challenging Geometry and Measurement Units on the Achievement of Grade 2 Students

The primary goal of Project M 2 was to develop and field-test challenging geometry and measurement units for all K–2 students. This article reports on the achievement results for students in Grade 2 at 12 urban and suburban sites in 4 states using the Iowa Tests of Basic Skills (ITBS) mathematics concepts subtest and an open-response assessment. Hierarchical linear modeling indicated no significant differences between the experimental (n = 193) and comparison group (n = 192) on the ITBS (84% of items focused on number); thus, mathematics concepts were not negatively impacted by this 12-week study of geometry and measurement. Statistically significant differences (p < .001) with a large effect size (d = 0.89) favored the experimental group on the open-response assessment. Thus, the experimental group exhibited a deeper understanding of geometry and measurement concepts as measured by the open-response assessment while still performing as well on a traditional measure covering all mathematics content.