Curated OER
The Truth About Triangles and Squares
Fourth graders investigate the patterns associated with both triangular and square numbers. They use counters as manipulatives to depict the numbers as needed but focus on problem solving using mental math techniques.
Curated OER
Ecological Organization
High schoolers explain the impact of ecological organization. In this web-based lesson, students work through a series of activities to explain how biotic and abiotic interactions occur in ecosystems.