Thirty fifth- and sixth-grade students were given extensive proactive instruction on the content of a computer-based problem-solving game called Rocky's Boots. Participants were then divided into three treatment groups that received either problem-solving training, problem-solving and self-monitoring training, or no further training. The monitored problem-solving group solved more complex problems than either of the other two groups, and they took less time to solve those complex problems. The specific impact of the monitoring training is discussed as evidence for the importance of strategy monitoring in learning to solve problems. Results are discussed as evidence of the potential of proactive instruction on problem-solving performance.