Will college students who set goals work harder and perform better? We report the results of two field experiments that involved four thousand college students. One experiment asked treated students to set goals for performance in the course; the other asked treated students to set goals for a particular task. Task-based goals had large and robust positive effects on the level of task completion, and task-based goals also increased course performance. We also find that performance-based goals had positive but small effects on course performance. We use theory that builds on present bias and loss aversion to interpret our results.