The authors investigated the effects of student spatial ability, as measured by Raven's Progressive Colored Matrices (J. C. Raven, 1938) and type of instructional program on geometry achievement. Sixth-grade students worked through either 6 instructional activities in Geometer's Sketchpad (Key Curriculum Press, 1993), a dynamic geometry program,…

Students enrolled in EXTRA, a tutorial program in basic reading and mathematics skills, were compared with non-EXTRA students to measure the program's success. EXTRA achieved success in mathematics tutorials but not in its reading program. Implications of findings are reviewed. (Author/DF)