Grades 6-9
35 activities—224 pages

Proportional Reasoning is abundant in real-world contexts. Investigations in this book invite students to actively explore, develop, and apply proportions. Students will be excited about working on proportions and percents instead of just reading and writing about them.

Six diverse sections are developed within Proportional Reasoning:

• Foundations—With paper clips and elastic, students develop numeric skills.
• Similarity—Using mirrors and shadows, students understand geometric applications.
• Enlargement—Students explore how projectors and computers produce proportional enlargements.
• Scale—Movies and models provide students with a context for scaling.
• Rates—With toy cars and bouncing balls, discover how rates are proportional.
• Human Proportions—Studying their own bodies, students recognize human proportion.

Students will be excited as they follow moving toy cars and put blocks behind their paths in one-second intervals in order to learn about rates in the exploration “Time Trials.” In the exploration “Percent Bands,” students will mark an elastic band to reflect percentages (10 percent, 20 percent, etc.) and then stretch the band to discover the percentages remain the same while the proportions increase. They will be able to use the band to determine percentages of other objects.

These hands-on activities keep students enthused about learning and provide a natural bridge to help students move from their numeric experiences in elementary school to developing algebraic concepts.