Scientists found fossils of plants more than 420 million years old—but plants existed for up to 100 million years prior to these fossils. Learn about the importance of plants to the entire planet. Viewing a presentation helps scholars...

Take a closer look at the life and presidency of George Washington with this great set of lesson plans and worksheets. The resource includes a timeline of the president's life and multiple opportunities for primary source and...

Learners investigate the characteristics of the tundra on the North Slope of Alaska. They conduct Internet research, develop a chart of the types of vegetation, plant growth, and fauna found on the tundra, identify examples in their own...