This study evaluated the impact of a computerized visuospatial memory training intervention on the memory and behavioral skills of children with Down syndrome. Teaching assistants were trained to support the delivery of a computerized intervention program to individual children over a 10–16 week period in school. Twenty-one children aged 7–12 years with Down syndrome were randomly allocated to either an intervention or waiting list control group. Following training, performance on trained and non-trained visuospatial short-term memory tasks was significantly enhanced for children in the intervention group. This improvement was sustained four months later. These results suggest that computerized visuospatial memory training in a school setting is both feasible and effective for children with Down syndrome.