Other
Universite De Montreal: Protist Picture Gallery
At this site from the Universite de Montreal, you can click on the name or picture to see images & data on each of the protozoa. Elementary teachers will need to guide their students through this information.
Other
Mbari: Rhodophyta, Red Algae
This site from the Monterey Bay Aquarium Research Institute defines red algae, habitat, orders and genera, and methods. The information that is presented is somewhat brief, but factual, and riddled with links to additional information.