Below are helpful wesites when identifying triangles...
Interactive:
http://www.ixl.com/math/grade-5/types-of-triangles
http://www.factmonster.com/math/knowledgebox/player.html?movie=sfw41507
Informative:
http://www.mathwarehouse.com/geometry/triangles/triangle-types.php
http://www.cliffsnotes.com/math/geometry/triangles/classifying-triangles-by-sides-or-angles