Water springs from the ground, creeks gurgle downhill, snow and rain make streams bigger, and then you have a river. But where does that river go? Step by step, Sally M. Walker's simple, scientifically accurate narration lets the youngest hydrologists follow water's movement from high land to the ocean, changing from a trickle to a torrent along the way. At each juncture comes the refrain: where's it going? Kim Smith's lush landscapes capture the water in motion and fauna nearby, from wading moose to leaping fish. A note to parents suggests bringing the learning to life by encouraging questions and observations of the natural world.