The research experiments on relational learning in young children contained in this report were guided by two major goals: (1) to examine the extent of conceptual transfer in preschool children, and (2) to explore the relation of both "acquisition" and "transfer" to chronological development. The performance of preschool children on several oddity tasks dealt with transfer between oddity problems in which stimulus types were Identity-Difference, Identity-Similarity, or Similarity-Difference. Based upon performance in these tasks, children were assigned to either of two groups and the relation of age to acquisition and transfer was explored, using the standard oddity presentation. A final series of five experiments were run with nursery school children investigating the possible perception of both the perceptual and numerical differences present in a standard oddity task as well as the variables controlling initial acquisition of a numerical difference problem. The data from these studies indicate that considerable cognitive evaluation is possible in preschool children. (Author/CS)