A review of nine major studies of preschoolers compares the predictive validity of achievement and psychoeducational tests in the identification of at-risk learners with the predictive validity of socioeconomic information. Findings indicate that tests used for special education identification have only a slightly better than chance prediction rate. More reliable predictors of school success are the race and educational status of the mother, the gender of the child, and the socioeconomic background of mother and child. The studies indicate that no test instruments can predict at-risk learners at an early age better than chance. Observations of children's abilities to follow direction, attend to tasks, visually and sequentially organize tasks, and systematically approach tasks may be the best indicators of early school success and failure. (Author/RH)