Concrete evidence of the effectiveness of geographic information systems in the curriculum is lacking. Research concerning the effectiveness of GIS technology and methods has been confined chiefly to anecdotal evidence from classroom observation. Experiments conducted in geography and special education courses in Boulder High School, Boulder, Colorado, USA, provide some of the first empirical and case study data as to the effectiveness of GIS in teaching spatial and temporal relationships. Preliminary evidence suggests that students working with GIS demonstrate increased use of maps as analytical tools.