Atmosphere

Gases that surround the earth


http://science.pppst.com/weather/atmosphere.html

compare and contrast atmospheres

http://www.kidsgeo.com/geography-for-kids/0050-mixture-of-gases.php

http://www.kidsgeo.com/geography-for-kids/0046-layers-of-the-atmosphere.php

Interactive
http://classroom.jc-schools.net/sci-units/atmosphere.htm