Activity
University of Guelph

Fish of Canada: Introduction to Fish

For Students 9th - 10th
Great site that provides all types of information on fish ranging from fish ecology to funky fish. Entails links to sites on fish evolution and morphology.
Activity
Other

Pet place.com: The External Anatomy of a Fish

For Students 9th - 10th
A very good overview of the class of fish, which includes a very good description of the external structure.