A study was conducted to examine young children's ideas about a psychology study in which they had participated, and to assess their perceptions about the voluntary nature of their participation. Subjects were 28 third-grade students and 28 fifth-grade students. Findings indicated that while no significant grade level differences existed in students' understanding of the purposes of the research, the responses of a sizable minority of third graders would not meet Weithorn's (1982, 1984) criteria for informed consent. Age and gender differences were found concerning ideas about withdrawing from the research. Although a majority of children at both grade levels felt they could withdraw, more girls felt that withdrawing was acceptable. Age differences were found in reasons for not withdrawing. Younger children spoke about enjoying the experience, whereas older children spoke of guilt or issues of commitment. It is concluded that, although children may be able to agree to participate in research by virtue of their knowledge about a study and its purposes, they may feel less free to withdraw. Decisions about withdrawing from research studies may have less to do with issues of boredom or discomfort and may be more directly related to moral development or understanding of contractual agreements. (RH)