Workbook
National Security Agency

Equations and Expressions

For Teachers 5th - 6th Standards
Learners demonstrate their knowledge pictorially, concretely, and abstractly in this unit meant to last three hours over three days. Using hands-on activities, manipulatives,  real-world applications, and problem...
Lesson Plan
Curated OER

Science: The Age of the Redwoods

For Teachers 9th - 12th
Learners discover how to estimate the age of redwood trees. They measure the trees' diameters by using string to calculate the circumferences. Students conclude by discussing the science of dendrochronolgy.