Geometric figures are formed on rectangular geoboards in order to study their features. There are investigations of the lengths of geoboard segments, congruence, and classification of triangle and quadrilaterals. Circular geoboards are used to explore the relationship between central angles and inscribed angles. Just for Fun: Tangram Figures

Pattern blocks and regular polygons from the material cards are used to construct regular and semiregular tessellations. The relationship among the angle measures of tessellating polygons is explored. Just for Fun: The Game of Hex

Models for the Platonic solids are constructed and used to examine properties of regular polyhedra. Students discover and apply Euler's formula and are introduced to the 13 Archimedean solids (semi-regular polyhedra). Just for Fun: Instant Insanity

Pattern blocks are used to form figures with line symmetry and rotational symmetry. Additional activities have students fold a piece of paper, make certain cuts, and predict the symmetries of the resulting figure before unfolding the resulting pattern. One of the patterns produces the eight-pointed wind rose. Just for Fun: Snowflakes

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Cutting off pieces of a cube made of clay or other material to determine possible cross sections is time consuming and inconvenient. Now you can experiment on a cube that can be sliced and rotated on the screen to observe cross sections.

In This Chapter

Geometric Figures
	Classroom Readings Interactive Math Applet Figures on Rectangular and Circular Geoboards Bibliography Regular and Semiregular Tessellations Bibliography Models for Regular and Semiregular Polyhedra Bibliography Creating Symmetric Figures: Pattern Blocks and Paper Folding Bibliography