This study tested predictions drawn from social identity development theory (SIDT; [Nesdale, D. (1999a). Social identity and ethnic prejudice in children. In: P. Martin, & W. Noble (Eds.). Psychology and society (pp. 92-110). Brisbane: Australian Academic Press; Nesdale, D. (2004). Social identity processes and children's ethnic prejudice. In M. Bennett, & F. Sani (Eds.), The development of the social self. London: Psychology Press]) concerning the development of young children's ethnic attitudes. Children aged 5, 7, and 9 years (N = 149) participated in a minimal group study in which they were randomly assigned to a team that had higher or lower drawing ability than a competitor team (social status). In addition, the competitor team was revealed to be comprised of children with the same (i.e., Anglo-Australian) or different (i.e., Pacific Islander) ethnicity as their own team (outgroup ethnicity). The children subsequently rated their liking for, and similarity to, the ingroup and the outgroup, and the extent to which they wished to change groups. The results indicated that children's liking for the ingroup was unaffected by age and outgroup ethnicity, whereas liking for the outgroup increased with age and was greater for same than for different ethnicity children. The children's attitudes toward changing groups were determined by status. The extent to which the findings provide support for SIDT is discussed.