Illustrative Mathematics
What is a Trapezoid? (Part 1)
Challenge your class to construct a definition for trapezoids. Looking at four examples and four non-examples, students individually create definitions and use them to classify an unknown shape. Allow for small group and whole-class...
Curated OER
House and Holmes: A Guide to Deductive and Inductive Reasoning
Test your pupils' reasoning skills with several activities and a quick mystery to solve. Learners watch and analyze a few video clips that demonstrate reasoning in action, practice deduction with an interactive and collaborative...
Illustrative Mathematics
What is a Trapezoid? (Part 2)
This collaborative activity investigates the meaning of a trapezoid and a parallelogram. It begins by presenting two different definitions of a trapezoid. Learners are to reason abstractly the difference between the two definitions and...
Curated OER
Symmetries of Rectangles
Learners explore mapping a rectangle onto itself using rigid motion concepts, geometric intuition and experimenting with manipulatives in a collaborative task.
101 Questions
Best Square
If you're a square, be the best square you can be! Young scholars develop a formula to determine the four points that make the best square that considers the area, perimeter, and other dimensions. They use their formulas to rank attempts...