One major long term objective is to develop and have available for extensive use, a preschool cognitive screening test which will more effectively identify four and five - year - old children who, absent any educational intervention, will experience academic failure, develop emotional and/or motivational disturbances, and be classified as either mildly retarded or learning disabled. The early identification of these mildly cognitively impaired children can be expected to at least reduce their cognitive impairment and thus eliminate or severely ameliorate the negative impact that continuous academic failure has on their mental state. In this proposal, the psychometric properties of a cognitive screening test will be evaluated by administering the screening test to both an experimental and cross validation sample, using scores to predict outcome (special education or not) and then validating those predictions based on the educational classification of those students in third grade. We will collect data which will allow us to determine the test's concurrent validity, predictive validity, construct validity, test-retest reliability and inter-rater reliability. We will use special education outcome to streamline the test to maximize its validity. In addition, the second goal of this project will be maintained in this proposal. Same age normally achieving, learning disabled and mildly retarded children will to be compared on a broad array of cognitive tasks in order to understand better how similar or different the two impaired groups are from each other and from the two normal groups. In addition, a normal, but low, achieving group will be added to help delineate the specific cognitive deficits associated with the LD group. These data have implications for decisions about the best conditions under which to provide special educational services for the mildly impaired groups.