Multiple schedules using continuous discriminative stimuli have been used to minimize children's disruptive requesting for teacher attention (e.g., colored floral leis; Tiger & Hanley, 2004; Tiger, Hanley, & Heal, 2006). The present study evaluated the effectiveness of, and children's preferences for, two multiple-schedule arrangements in which brief experimenter vocalizations served as discriminative stimuli. Results showed that brief signals were highly effective discriminative stimuli for 3 of the 4 children, and that all children preferred one or both variations of the multiple schedule to a control arrangement. For 1 child, highly discriminated responding was achieved only when continuous signals were introduced. (Contains 2 figures.)