Rotter's social learning theory was used as a basis for studying the effects of locus of control on the frequency of the responses of undesirable behaviors. Subjects, 12 fifth graders who had operant levels higher than desirable were monitored by either themselves, a peer, or by no agent for a period of eight weeks. Classes of behaviors (socially-oriented and self-oriented) were studied. An analysis of variance was used to compare the frequencies of the responses for the various subsamples from baseline to termination of the monitoring. A significant interaction term suggested greater decline for "public" behaviors than for "private" ones. None of the following hypotheses was supported: (a) the reduction of negative behaviors through self-monitoring positive and incompatible behaviors will be greater for internals than externals; (b) the reduction of negative behaviors through peer-monitoring of positive and incompatible behaviors will be greater for externals than internals; (c) the reduction of social-interactive negative behaviors will be greater than private negative behaviors for externals. (Author)