Focus: In this unit, students extend their understanding of shapes and geometric measurement by applying their knowledge of proportional relationships to the study of circles. The unit begins with activities designed to help students come to a more precise understanding of the characteristics of a circle. They measure, draw, and investigate the relationship between the circumference and diameter of different circles with the use of compasses, tables, and graphs.
The second section of the unit involves students’ exploration of area and, in the third section, students use formulas for the area and circumference of a circle to solve abstract and real-world problems. Throughout the unit, students discuss their mathematical ideas and respond to the ideas of others. To conclude the unit, students apply what they have learned by designing stained-glass windows within a set of criteria, including size, shape, cost, and material requirements.
Number of Lessons: 11
Lesson Time: Approximately 45 minutes. Please note that each lesson is designed for one instructional block, and may be divided into shorter segments based on teacher pacing and student needs.
Additional Search Terms:
relationship • perimeter • radius • diameter • circumference • center • constant • pi • proportion • half-circle • rotation • approximation • estimate • area of a circle • squared • formula • design • mathematical practices