Illustrative Mathematics
Similar Triangles
Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...
Teach Engineering
Stay in Shape
Using their knowledge of right triangles, pupils find out how far a ship is from a light house. Class members determine how far around the world a ship would be sailing at a constant speed.
Teach Engineering
Connect the Dots: Isometric Drawing and Coded Plans
Individuals discover how to draw cubes on triangle-dot paper. They use cubes to build structures and draw corresponding isometric drawings on dot paper in the second lesson of the series of five. The activity also introduces the concept...
Teach Engineering
Catching the Perfect SAR Waves!
Zero in on an interesting resource involving radar technology. Groups construct a radar sensing unit and learn to calibrate the system. Using the radar system and the Pythagorean Theorem, they calculate distances between objects.
Curated OER
Mt. Whitney to Death Valley
This is an intriguing problem that brings together real-world data, technology, and mathematical problem solving. If visibility wasn't an issue, could you see from the highest point in the lower 48 states, Mt. Whitney, to the lowest...
Beauty and Joy of Computing
Sprite Drawing and Interaction
Discover how to program objects to move on a screen. In the second lab of a five-part unit, each learner uses block instructions to program a sprite to follow their mouse (cursor). They investigate how to use these same block...
Teach Engineering
Straw Bridges
Pairs work as engineering teams to design and build model bridges from drinking straws and tape. In this third segment in a series of 10, teams compete in an attempt to build the strongest bridge. To help with the design, the groups...
Teach Engineering
Let's Take a Spin: One-Axis Rotation
Investigate the effect of one-axis rotations on geometric figures. Scholars learn to use snap cubes and the right-hand rule to draw figures after rotations about the x-, y-, or z-axes. They try their hands at examples created by the...
National Council of Teachers of Mathematics
The Math Forum: Line Symmetry
This site from The Math Forum is a great site if you are looking for activities to engage your students in learning about line symmetry. Peruse this collection of activities for one or two or four that would be right for your students....