General sources of information:

Animal Diversity Web - searchable data base - University of Michigan- Museum of Zoology
ASPCA's Animaland.org -This child-friendly site offers interactive information on careers, animal care, and general information about animals.
Animals - A to Z- by Oakland Zoo - Birds, mammals, marsupials, and reptiles form the list that leads to detailed photos and information.
Desert Animals and Wildlife - excellent page with easy-to-read information
Jurica Nature Museum  contains information about all of the specimens on exhibit (and perhaps, more) in the museum.
Mammals of the Boreal Forests - Canadian - Excellent
National Geographic Creature Feature - features many animals - Hold mouse on photo of animal to find its name. Excellent!! 
National Image Library - copyright free pictures from the library of wildlife, scenes and conservation issues - U.S. Fish & Wildlife.
Nature Works - information easily readable by younger students
SeaWorld/Busch Gardens   Animal information database. Excellent!!

African Animals:
African Animals Enchanted Learning site

Bats
Bat Conservation International - Bat links and information on specific bats -High reading level.
Bats Bats everywhere Basic bat information - by Bats 4 kids.

Bears
Bears - by BBC Online Nature Wild Animals

Beavers
Beavers - Environmental Education for Kids - elementary level
Beavers - by Nature Works - good for elementary grades
Beavers - Animal Tracks Den -good for elementary grades
Beavers - Wildlife Fact File - Canadian animal
Beavers - Enchanted Learning - excellent information for elementary grades
Beavers - University of Michigan -Animal Diversity Web - higher reading level
Beavers- Wetlands & Wildlife Home Page - higher reading level

Bees
Honeybees - excellent information and links.

Cats
Bobcats
Cheetah
Jaguar
Lion
Lynx
Mountain Lion
Tiger
Leopard
Snow Leopard
Cougar

Caribou
Being Caribou - Caribou Migration - excellent site to fully understand this Arctic animal
Porcupine Caribou Herd - includes an information slide show, text references and more...
Caribou Commons - information discussing problems in the Arctic affecting the caribou

Dolphins
Bottlenose dolphin
Dolphin Fact Sheets

Endangered Species:
Endangered Species - Kids' Planet - fact sheets
Threatened and endangered species - Environmental Education for Kids - EXCELLENT
Threatened Species - The Red List identifies particular species at risk of extinction. From the International Union for Conservation of Nature and Natural Resources.

Fish
FishFAQ -Northeast Fisheries Science Center - These are the Most Frequently Asked Questions - contain some fascinating facts about fish.

Pandas
Giant Panda - World Wildlife Fund is providing the information.
Giant Panda information by Zoo Atlanta
Giant Pandas at the Smithsonian National Zoo
Panda - by the Animal Diversity Web - University of Michigan.
Panda Central - Zoological Society of San Diego - excellent information about pandas.
Project Panda - information provided by Animal Planet

Polar Bears
Polar bears
Polar Bears - National Geographic
Polar Bears - by BBC Online Nature Wildlife
Polar Bears Alive - for polar bear lovers all over the world.
Polar Bear information  Includes many links.
Polar Bear Invasion  PBS Nature series.
Polar bear tracking - Space for Species - filled with information as well as tracking several species
Polar Bear Central - World Wildlife Federation - excellent site
Polar Bears International - EXCELLENT factual information

Primates
Primates - Find out Why - TIME for Kids and National Science Foundation presents information and activities.Sharks
Shark, Great White  California Academy of Science.

Tigers
Tigers

Whales
Baleen whale
Beluga whale
Killer Whale
WhaleNet Fr/Eng for students and teachers
Whales Fact Sheets

Wolves
Brother Wolf
International Wolf Center
Kids Only - Wolf Information
Mission: Wolf
Searching Wolf - Wolf pictures
Wild Wolves - by NOVA Online
Wild World of Wolves
Wolf's Den
Wolf Pack Picture Gallery
Wolves - pictures
Wolves Online
World of Wolves