Many schools throughout the United States are mandated to hold drills, or operational exercises, to prepare for fires, earthquakes, violence, and other emergencies. However, drills have not been assessed for their effectiveness in improving preparedness at schools. This mixed-methods study measures the quantity and the quality of drills in an urban school district in Los Angeles. Compliance with California mandates was fair; most schools barely met requirements. Drills were not used as opportunities to improve procedures. Sites neither conducted any self-assessments nor made changes to procedures on the basis of performance. Suggestions include developing realistic simulated exercises, debriefing, and better school accountability for drills.