Spatial ability and transformational geometry

New technologies in education are placing more emphasis upon visual and spa tial skills, those required to inspect, encode, transform, and construct in formation in visual displays. They do this by presenting students with lear ning material embedded in complex visual displays and hypermedia, and by re quiring students to navigate through virtual space. These developments make it important for us to learn more about the underlying nature of visuospat ial ability, how it is related to academic performance, and how it can be i mproved. This paper explores these issues in the context of instruction in transformational geometry upon geometry performance and spatial ability of Grade 7/8 students. The instructional conditions were (a) a traditional tex tbook approach involving paper-and-pencil tasks and verbal instruction (Tra ditional Group), and (b) an approach incorporating object manipulation, and visual imagery, which was designed to encourage spatial thinking (Spatial Group). Multiple regression results indicated that posttest geometry perfor mance was predicted by pretest geometry, pretest spatial ability, and the i nteraction of pretest geometry and instructional condition; the interaction indicated that high prior knowledge subjects performed better in the Spati al group, low prior knowledge subjects in the Traditional group. Posttest s patial ability was predicted by handedness, pretest geometry, pretest spati al abi and the interaction of pretest spatial ability and handedness, inter action indicated that less right-handed subjects of low spatial ability imp roved on spatial ability more than their more right-handed peers. With resp ect to geometry instruction, we suggest that some students may require pr i ol verbal instruction to build up a knowledge base of spatial and geometric al concepts. Mor-e broadly, these results raise concerns about the needs of students who may be disadvantaged in complex visual instructional settings requiring sophisticated visuospatial skills. We suggest that these skills are improvable to some extent, but that this will require deliberate instru ction.