Prior research has indicated that, although negative mood induction procedures reliably lead to enhanced helping in adults, such procedures do not produce increased helping in young children. Consistent with the negative state relief model, it was expected that, relative to neutral mood subjects, children in a negative mood would be more generous if the helping opportunity offered the potential for direct reward through social approval. This expectation was supported in a pair of studies wherein children in Grades 1-3 were asked to imagine either neutral or sad experiences and were then given the opportunity to be charitable either in public or private. The second experiment provided evidence that the enhanced public helping of negative mood subjects is more parsimoniously interpreted as an attempt to remove negative mood than to repair public image. Finally, a three-step account of the development of altruism as a self-reward was proposed. Initially, helpfulness was found to be rare because it involved the loss of rewards. At the second step, children, usually those in primary grades, became aware that helping could lead to systematic social reinforcement, although they may be less helpful when in a negative mood. After sufficient experience with external reward for charitable action, the behavior itself assumes the quality of a secondary reinforcer occurring with increased frequency in all moods. (Author/BEF)