At 2,300 miles long, the Mississippi River is the second longest river in North America. People have tried to control the flow of the river to prevent floods and keep it flowing towards port cities. This can lead to loss of land in the Mississippi Delta. Examine images and maps from NASA showing the meandering river and its distributary and compare images from 1976 and 2001 to see the changing delta. Also included are teaching tips, words to know, and background information for the teacher.