This study examined children's use of category information as a discrimination cue to avoid intrusions in recall and false alarms in recognition of items outside given categories. Forty-eight children in grades 1 and 4 were administered one of three conditions of a recognition task in which all study words were members of one of two familiar categories. Conditions were: (1) a fully categorizable list of words (animals and occupations) along with full information as to the categorizability of the list; (2) the same categorizable list but without such information; or (3) a partially categorizable list in which that category information could not function as an effective discriminative one. All children were given the same recognition test list that included old words, new words taken from the study categories, and new words not from the study categories. Analyses of error patterns indicated that in all three conditions children extracted and used category information, but that only in the Categorizable Informed condition did category information function as a discriminative cue to avoid false recognition of new words outside the study categories. (Author/SB)