This is a free program taken on a CD-ROM collection of over 200 mathematics puzzles, available from 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 puzzle, students solve cross-number puzzles by evaluating simple expressions. Program uses only positive integers. You can view a screenshot of this program by clicking here.