Forty reflective and 40 impulsive children were assigned to one of four treatment conditions. The learning task employed a list of 25 familiar objects, five instances from each of five categories. The four treatments were Randomized-No Instructions, Randomized-Instructed, Blocked-No Instructions, and Blocked-Instructed. Results support earlier findings that retention and clustering are facilitated by a blocking technique. Clustering was also improved by instructions. For free recall however, instructions aided impulsives but hampered recall for reflectives. This suggests the use of different organizational strategies by people differing in cognitive tempos. Free recall was no better when instructions were given than when they were omitted; however, cued recall was facilitated by instructions. Support for a retrieval deficit hypothesis is indicated. (Author)