Bat Conservation International - Information on bats and how they are being protected.  This site contains actual audio tape of bat calls.

Bat World Sanctuary - Information on bats, including a good page on the myths and facts of bats.

Bats - A Thematic Resource for Students and Teachers - Leads to other great links about bats.

University of Michigan's Zoology Information on Bats - The content is written for adults, however, there are great photographs of different species of bats.

Bats! Strange and Wonderful by Laurence Pringle.
Wonderful illustrations and information on bats.

Bats by Gail Gibbons.
Great informational book on bats.  

Shadows of Night: The Hidden World of the Little Brown Bat by Barbara Bash.
Engaging illustrations in this factual story of the little brown bats.

Screech! A Book About Bats by Melvin and Gilda Berger.
Lots of information is contained in this "Hello Reader" book, as well as amazing photographs.

Bats: Shadows in the Night by Diane Ackerman.
The photographs are the highlight of this book, as the text is for older children.

Stellaluna by Janell Cannon.
The touching story of a baby bat who gets separated from its mother and befriends a nest full of baby birds.  It's a wonderful lesson on differences.

Amazing Bats by Frank Greenaway.
More great information and photographs.

The Magic School Bus Going Batty : A Book About Bats (Magic School Bus) by Nancy E. Krulik.
Magic School Bus style, Ms. Frizzle and her class have a nocturnal adventure and learn about bats.

Zipping, Zapping, Zooming Bats (Let's-Read-And-Find-Out Science, Stage 2) by Anne Earle.
This book contains good information on the brown bat.

Beautiful Bats by Linda Glaser.
Wonderful watercolors help to share the facts about bats.

Bat Jamboree by Kathi Appelt.
A fun counting book about a bat jamboree!

Bats Around the Clock by Kathi Appelt.
This fun book contains a lesson on telling time.

Bats on Parade by Kathi Appelt.
A counting lesson, and for older children, a lesson on multiplication.