Abstract:We discuss our experiences in which students of a programming course were asked to submit both an implementation as well as a test set. A portion of a student's grade was then devoted both to the validity of a student's program on others' test sets, as well as how that student's test set performed in uncovering flaws in others' programs. The advantages are many, as this introduces implicit principles of software testing together with a bit of fun competition. The major complication is that such an all-pairs execution of tests grows quadratically with the number of participants, necessitating a fully automated scoring system.