Conservation and Scouting go hand in hand. Since getting outdoors is a big part of the Cub Scout and Scouts BSA programs, it makes sense that we should teach Scouts about protecting our natural resources.
The US Fish and Wildlife Service has an Endangered Species Page where you can look up endangered species in your state or even your county. There is also a Weird and Wonderful Wildlife Page on the site where kids can learn about 14 different endangered species and play some games to find out even more.
So if your unit is studying endangered species for requirements or just to learn more about conservation, check out those pages from the US Fish and Wildlife Service.