February 26th, 2007 by Dan Meyer
Why We're Here:
- We're going to review area.
- We're going to determine the area of regular polygons.
- Remote Control Car
- Opener + Review (15 minutes)
- Race Car Math (30 minutes)
- Break (5 minutes)
- Show and Tell (1.5 minutes)
- Polygon Notes (20 minutes)
- Polygon Classwork (30 minutes)
- 1680. Boston Globe. Ask them to convert this to hours per day. Lots of ways to solve a and b. Entertain all of them.
- Other secondary rules: have the driver pick one place to steer and stay there; thumbs off the control sticks when the judge calls time, or he awards five bonus seconds to the other team. Be quiet as the solution is explained or the other team is awarded five bonus seconds.
- All work and no play …
- #8 is fun as they all wonder how to solve for area without the height. If no one in your entry-level Geometry class answers “30 square millimeters,” you’re the winner.
- In one class, I started by deriving a formula (basically flipping this slide with the next one) and then going for a specific case. The next class I pulled a switch and everyone was, foundationally, a little better off. Ask here: what shape can you split the regular polygon into?
- New vocabulary. Now develop the formula at the board using these variables. Talk about p = ns
- Ask them to ID the building. After they answer, the Pentagon, the teacher is encouraged to ask obliviously, … and what kind shape is the Pentagon?
- They built twice as many bathrooms as necessary due to segregation. The center was thought to be the most likely site of a nuclear attack and called ground zero. The rings are named A-E from the center outwards.
Notes & Revisions:
- Several values corrected per David's suggestion. Thanks, David.