The RAP Program is conducting a research study of the antipsychotic medication Aripiprazole. This drug has been approved for treating symptoms associated with schizophrenia and is associated with fewer side effects. This study will explore how well Aripiprazole treats symptoms of early-onset psychotic disorders as well as symptoms that may indicate risk for such disorders, including unusual thoughts, suspiciousness, perceptual abnormalities, social isolation, and sudden changes in functioning.