Solve & Swat is a powerpoint that you can project onto a wall. Split the class into two teams. Send one person from each team up to the board. Give each team member a fly swatter. As the question comes up on the screen there will also be four multiple choice responses. The first team member to swat the correct answer and explain why it was chosen will earn a point for their team. Each person only gets one guess. If both team members answer incorrectly, someone from the class can answer for a personal extra credit point.