Poor class attendance is detrimental to student success. This is especially true in entry-level college mathematics courses, where habitual non-attendance can have lasting effects that greatly limit a student's options for continued academic success. The purpose of this study was to design an attendance incentive and to evaluate its impact on student retention and performance in a freshman precalculus-trigonometry course. The attendance incentive, which the authors called "House Cash," was designed to minimize the grade inflation that is often associated with extrinsic rewards and also to eliminate the instructor's burden of maintaining daily course attendance records. Using a purposive sample of 131 participants, they found that both retention and performance measures in the House Cash course sections were higher than historical averages for the course. (Contains 1 figure and 6 tables.)