Four high school special education teachers in the Vocational Education Program in the South Bend Community School Corporation participated in a mathematics program. They then conducted classroom research related to their inservice activities with their mildly handicapped students. Teachers used manipulative materials in their inservice sessions and indicated positive attitudes toward their use with low achievers. Each teacher selected a minimum of 10 students for participation in the study; the entire class participated in the activities. Focus of the study was student achievement on computation with whole numbers. Each teacher determined the format for use of manipulatives, such as Try-A-Tile Cards, math match card games, pathway activities, calculators, and dice games. Increases in achievement on computations were obtained on all subtests and composites with one exception. Results lent support to the notion that use of mathematics manipulatives with slow learners can improve computation skills. In addition, classroom activities created a high level of interest in mathematics among many students. (YLB)