Rivers flow downhill, but why are there so many curves? The video explains how a straight river with only a tiny change begins to curve. It introduces the patterns all curving rivers follow all over the planet and other planets. 

Get wet with Bill Nye, the Science Guy, as he follows the flow of rivers and streams. Bill tracks the origins of these bodies of water and explains what impact they have on humans. [23:07]

Narrated animation that visually explains how a check valve opens and closes to ensure that water flows only in one direction in a pipe. (30 secs) Uses Quicktime.

Watch these children build two dams, and then see how they play a trick! [1:27]

Learn how water speed determines how rocks, sand and gravel are deposited along a riverbed. Watch two kids use the scientific method to find out why there are different rocks in different rapids.

Observe how rivers meander and how the water deposits rocks and pebbles on the inside of each curve. Watch kids use the scientific method to find out how rivers affect the earth's surface.