This is a free program taken from a CD-ROM collection of over 200 mathematics puzzles, available on the developer's Web site. Developed by a veteran teacher, these visually-oriented puzzle games have a simple interface and are designed to provide math problems in context to middle-school (grades five through nine) students. In this particular program, students are given the radius or diameter of a circle, as well as the measure of a central angle, and must find the area of the circle, the area of the sector defined by the central angle, the circumference of the circle, and the length of the arc defined by the central angle. All answers are rounded to the nearest hundredth. You can view a screenshot of this program by clicking here.