This paper compares LD and non-LD peers on eight variants of the oddity task. This study is part of a larger programmatic research effort aimed at the development of a screening test to detect preschool children who currently pass existing screening tests but, nonetheless, subsequently experience school failure. The theoretical orientation of this approach is to assess active, ongoing cognitive processing ability. The oddity task, which can be structured to assess such processing ability, was evaluated in the present study as a potential component of this screening test. Consistent with a priori predictions, the data resulted in strong group and developmental differences. Oddity performance increased over age, with the non-LD children performing consistently better than their LD peers at each age. Perceptual and conceptual factors were manipulated across the oddity variations, and both factors contributed to group differences. These results were discussed in relationship to early diagnosis and prognosis for learning disabilities that might result from deficiencies in abstract processing ability.