Described are a discrete group of isometries that fix a line but do not stabilize a point. Each type is accompanied by an example of their representation in concrete form which served as material on which young children could operate. Pupil responses to each situation are provided. (CW)

This 19-page workbook presents the elementary student with topological concepts through sequences of pictures with related questions. Generally the questions ask, "How are the pictures different?" and "How are they the same?" Several topological concepts are presented in this manner: connectivity, number of holes, closed and open curves, networks,…

A method for helping students to find formulas involving symmetry under various conditions is explained. Necklace symmetries, orbit counting, tetrahedra and cubes, relationship patterns, and finding patterns are discussed. (CW)