This study continues an investigation of how spherical units, compared to cubical units, can facilitate students' units-locating and organizing units in composites. We analyze how Norwegian grade 3 students enumerate 3D arrays with cubical and spherical units. Our results show how spherical units can act as perceptual clues that facilitate…

First-year engineering (FYE) students are routinely screened for spatial ability, with the goals of predicting retention in the major and identifying those who need supplementary spatial instruction. Psychometric tests used for such screenings are often domain-general measures that lack diagnostic information to inform remedial instruction. A new…