In this study, we compared the effects of simulator-based virtual ultrasound scanning practice to classroom-based hands-on ultrasound scanning practice on participants' knowledge of FAST window quadrants and interpretation, and on participants' performance on live patient FAST exams. Twenty-five novice participants were randomly assigned to the simulation-practice condition and 24 participants to the classroom-practice condition. Participants were mostly medical school students, with some nursing students. Participants who received simulation-based practice scored significantly higher on interpreting static images of FAST windows. On live patient exams where participants scanned the RUQ, LUQ, and suprapubic quadrant of a normal patient and an ascites positive patient (6 quadrants total), there were no statistical differences between the two conditions on scan time, window acquisition, and window interpretation except for the following: the classroom-practice condition had shorter scan time for the LUQ, and a higher number of participants attaining high window quality on the RUQ (normal patient only) and suprapubic quadrant (positive patient only) and correct window interpretation on the LUQ (normal patient only). Performance was statistically similar on all other window quality and window interpretation measures on the other quadrants. Overall, classroom-based practice appeared to promote physical acquisition skills (e.g., acquiring a window) and simulator-based practice appeared to promote window interpretation skills. The simulator used (SonoSimulator[TM]) was well received by participants and appears promising as a training tool not only to increase probe time, but also to increase exposure to FAST windows reflecting various anatomy and disease states. Appendices include: (1) Posttest Form (Knowledge of Ultrasound and Background Survey); (2) Prior Knowledge of Anatomy Items; (3) Participant Feedback Form; (4) Participant Comments; (5) Picture of a Classroom Practice Session; (6) Picture of the Lab Setup; (7) Classroom Practice Observation Form; (8) Performance test Observation Form; (9) Picture of the Simulation Setup; (10) Simulation User Interface Screenshots; (11) Simulation Condition Directions; (12) Ultrasound Simulation Report; and (13) Sonographer Feedback Form. (Contains 11 tables, 3 figures and 3 footnotes.).