Five sets of activities for students are included in this document. Each is designed for use in junior high and secondary school mathematics instruction. The first is concerned with the use of models in mathematics. The second contains a variety of activities involving polygonal numbers. The third set of activities includes a variety of games for which the students are to decide if the game is fair (a game for which a player has a fifty-fifty chance of winning). The fourth set of activities is related to geometry with an emphasis on circles. The fifth set of activities involves punching paper to explore numerical patterns. (RH)