http://www.bbc.co.uk/schools/scienceclips/ages/7_8/rocks_soils_fs.shtml This site is a fun interactive site on different tupes of rocks
http://www.quia.com/rr/38064.html This site is a great interactive site that is a question and answer style
http://www.cotf.edu/ete/modules/msese/earthsysflr/rock.html This site has a great rock-cycle diagram and important information