Investigated here are some of the results which can be obtained using the double-sided straight edge. Seventeen possible constructions are presented with solutions or partial solutions given to most. (MP)

Possible ways of mechanization for counting using a binary system are discussed. Shows a binary representation of the numbers and geometric models having eight triples of lamps. Provides three problem sets. (YP)

Various methods for solving the problem of finding when the hour and minute hand of a watch have the same direction are explored. The relationship of these problems to the educational environment and the maturity of the student are discussed. (CW)

The last 13 of 32 exercises of a course designed to give a wide range of skills in deductive, inductive, and indirect methods of proof in geometry are presented. (MP)

A program is outlined for the treatment of Tessellations. Major topics are: Introduction; Tessellations; Regular Tessellation; Semi-Regular Tessellations; Nonregular Tessellations; and Miscellaneous Tessellations and Filling Patterns. (MP)