Students study the benefits of estuaries. They construct a saltwater food web, and complete worksheets and a quiz.

Students make a clay model and a geographic map of a watershed. They talk about the differences between the two representations and the potential human threats to watersheds.

Pupils understnad the importance of keeping our rivers and streams pollution free by remembering the major rivers of northeast Kansas. The see how the rivers contain particles of every substance that drains into them.

Lake Mattamuskeet-so named by Algonquian Indians-is North Carolina's largest natural lake. The ancient body of water has not escaped man's intervention. Originally, Mattamuskeet was a shallow, self-contained lake without creeks or rivers...