This study was designed to assess the relative effectiveness of four components of pretraining on a subsequent simultaneous discrimination and reversal: (1) making same-different judgments about the two stimuli; (2) making a specific observing response to the critical feature of the stimuli; (3) simple familiarization with the stimuli; and (4) developing a set to compare stimuli. Seventy-two first-grade children served as Ss. Two sets of stimuli were used: line drawings of cats and line drawings of children's faces. Although none of the pretraining conditions had a facilitating effect for Ss seeing the faces, there were significant facilitative effects for Ss seeing cats. Specifically, the three pretraining conditions involving same-different judgments facilitated both learning and reversal, whereas the effect of "observing response alone" pretraining had no such facilitative effect. (Author)