Two online resources for kids about endangered animals are the U.S. Fish and Wildlife Service's Homework Help page and Kids Discover's Endangered Species Spotlight. These resources have information on specific endangered species, as well as on both widely-accepted and highly-debated causes for the sharp decline in some populations.
The three components of the USFWS's Homework Help page are species information, a link to the website's digital library where kids can find photos of endangered animals, and the Weird & Wonderful Wildlife interactive game. Kids Discover's Endangered Species Spotlight has captioned photos of endangered wildlife and a short endangered species quiz.