Instructional Unit: Grouping of Two-Dimensional Shapes

By: Tim Lehman

The following unit is intended for a geometry class studying two-dimensional shapes. Students are assumed to have an understanding of Geometer's Sketchpad and constructions.

Most of the lessons use technology in some form. However, many could be accomplished if it is not available. For example, the exercises of lesson 2 may be completed using graph paper instead of GSP. The lessons are divided where I saw natural divisions, not to fill a single period. Depending on class period length and the depth the instructor wanted to study each topic, lessons may be stretched over several days or combined to fill one day.

**Lesson 1**: Introducing two-dimensional shapes and terms

**Lesson 2**: Similarity and congruence

**Lesson 3**: Perimeter and circumference

**Lesson 4**: Introduction of area

**Lesson 5**: Pythagorean Theorem

**Lesson 6**: Area of regular polygons

**Lesson 7**: Area of circles

**Lesson 8**: **Contextual Teaching and Learning in: **Working
at a golf course