This study was conducted in order to compare the effects of immediate practice and delayed practice on retention of learned rules. Seventh-grade students (N=103) were instructed on three rules of operation with exponents by programmed text. These subjects were randomly assigned to five treatment groups: (1) no practice, (2) one practice trial on the first day, (3) five practice trials on the first day, (4) one practice trial on the fifth day, and (5) five practice trials on the fifth day. On the twenty-first day of the study, all subjects were given a retention test. Findings indicated that delayed practice was significantly more effective than immediate practice as a means of providing for retention. Five delayed trials were not more effective than one delayed trial, nor was immediate practice more effective than no practice. (SD)