Geometry Tools: Angles & Reflections
Students learn about common geometry tools and then learn to use protractors (and Miras, if available) to create and measure angles and reflections. The lesson begins with a recap of the history and modern-day use of protractors, compasses and mirrors. After seeing some class practice problems and completing a set of worksheet-prompted problems, students share their methods and work. Through the lesson, students gain an awareness of the pervasive use of angles, and these tools, for design purposes related to engineering and everyday uses. This lesson prepares students to conduct the associated activity in which they “solve the holes” for hole-in-one multiple-banked angle solutions, make their own one-hole mini-golf courses with their own geometry-based problems and solutions, and then compare their “on paper” solutions to real-world results.
The tools of geometry.Copyright 2012 Louisa Puffet, CC BY NC-SA 3.0 http://iteach.org/mrspuffett/geometry/images/geo-tools.jpg http://iteach.org/mrspuffett/geometry/index.html
Ancient Egyptian and Roman engineers used geometry tools to create impressive structures and sites that still stand today. Over time, these tools became more complex and enabled more accuracy and greater design precision. Today, the same tools are used by engineers for creating precise design drawings for modern infrastructure, systems and products. Engineers rely on their tools to provide consistent ways of measuring, especially aspects such as length and angles, to enable modern feats of engineering from skyscrapers to satellites. These tools also help us communicate across different spoken languages and cultures since they are universal—that is, 30° in the U.S. is the same as 30° in China.
After this lesson, students should be able to:
- Use geometric tools to measure and draw angles.
- Describe how to reflect points and lines using a geometry tool.
- Explain how engineers use geometry tools to design everyday products and infrastructure.