Sitomer, Mindel

Defines rays and segments, explains how they can be put together to form polygons, and describes how to make a clockboard and use it to create various geometric designs.

Defines spirals, describes the different kinds found in nature, and discusses man's use of this concept.

Discusses the importance of zero in the decimal system and its many uses.

A simple description of the different types of symmetry, including line, point, and plane.

Simple experiments illustrate the concept and characteristics of the circle.

Briefly explains the matching and comparison of quantities, the naming and ordering of numbers, and counting--all steps in the history of numbers.