This paper examines the acquisition of superstitious behavior in young children. Six preschool children were exposed to a 15 minute fixed-time inter-reinforcement interval (FT-15") schedule while another six preschoolers were exposed to a 30 minute fixed-time inter-reinforcement interval (FT-30") schedule. In a free-operant laboratory setting, a mechanical clown delivered marbles, which the children could later trade for toys, according to one of the two schedules. All sessions were videotaped and scored for particular superstitious behaviors (for example, touching the clown and making faces). Since no differences emerged as a function of FT interval length, all twelve children were grouped for analysis. One third to one half of the twelve children showed evidence for acquistion of superstitous behaviors; four children showed some dominant behaviors but it was not possible to clearly ascribe the word superstitous to them and three children showed extremely low frequencies of any particular behaviors. An independent assessment of reinforcement effectiveness was conducted, and inter-observer reliability was provided. (Author/MP)