This research examines whether children's perception of similarity is related to their preference for stimuli (which stimulus is liked best), how these preferences and perceptions develop, and whether preferences or perceptions are related to the efficiency of learning. Multidimensional scaling procedures are used to determine the importance of the dimensions of color and form in children's perceptions, and how that importance changes over the years four to six (in a longitudinal study). Finally, earlier studies of the relationship between preference and learning are being reexamined using multidimensionally scaled stimulus values (for preference and perceptual similarity) as learning task stimuli to determine whether children's learning is more a function of what children like to look at (preference) or how they organize the perceptual world (based on perceptual similarity). The significance of this research is in the experimental attempt to: a) define how children perceive color, forms, and combination color-form stimuli; b) describe the relationship between what children like to look at and what they perceive to be similar; and B) to examine the relationships among similarity. preference, and learning. Thus the experiments are providing evidence on how these cognitive subprocesses develop and are organized.