Students with poor spatial abilities experience a barrier to academic success early in the STEM curriculum. However, Sorby et al. report that even brief training can improve spatial reasoning in students who lack them. Further, the National Research Council recommends that spatial thinking skills be taught at all educational levels. Halpern defines spatial ability as a heterogeneous cluster of cognitive skills. "Mental rotation" and "orthographic projection" are two of these skills. Mental rotation is the capacity to mentally rotate a two- or three-dimensional object. The orthographic projection skill is the ability to represent three-dimensional objects in two dimensions. These skills are important across the STEM curriculum, and in physics and astronomy these skills have particular relevance.