Attention Deficit Hyperactivity Disorder (ADHD) is one of the most commonly diagnosed disorders among children today. Stimulants are commonly prescribed to children with ADHD to improve attention span and decrease distractibility, hyperactivity, and impulsivity. Given the increased use of stimulant medication, school personnel need to be aware of the implications and limitations of the stimulant medications on a child's academic and behavioral performance. In this study, pre-service school personnel's awareness of the symptoms and causes of ADHD and the effects of stimulant medication was examined using a 13 item questionnaire developed by Snider, Busch, and Arrowood (2003). Further, the differences in knowledge levels between the Graduate and Undergraduate students were examined. The sample consisted of 76 Undergraduate and Graduate students majoring in Special education, General education speech and Language pathology, and School psychology. The findings indicated that pre-service school personnel (a) had higher knowledge scores than reported in previous literature and (b) were less aware of the lack of long-term efficacy data and the side effects of medication. Independent Samples "t" test indicated that there were no differences between the graduate and undergraduate student groups on the overall knowledge scores. Based on the results, it is recommended that the side-effects of stimulant medication should be incorporated within the teacher education curriculum.