The purpose of this research was to determine what effects, if any, widening or narrowing the response repertoire has on measures of IQ and problem solving of preschool children. It was predicted that response widening, or creative/divergent thinking, would have a positive effect on IQ and problem solving. Forty-one preschool children 3 to 6 years of age were divided into three matched groups. One group was exposed to response widening tasks, while a second group was exposed to response narrowing tasks. A third group served as control. Special training with response narrowing and response widening tasks was provided for a 3-hour period twice each week for 6 weeks. The Wechsler Preschool Primary Scale of Intelligence, the Torrance Thinking Creatively with Action and Movement, the convergent ad divergent subtests of the SOI Learning Abilities Test, and the Kaufman Assessment Battery for Children were administered during pre- and post-tests. Results indicated that response widening had a positive effect on IQ, with training being most effective for younger children with average IQ scores on the pre-test. Contrary to the hypothesis, problem solving increased for all groups. (Author/RH)