The Berenstain Bear Scouts work with Grizzly Gramps and Professor Actual Factual to save Giant Bat Cave from another of Ralph Ripoff's moneymaking schemes.
The kids in Ms. Frizzle's class learn lessons about bats when they accidently transform the Magic School Bus and then themselves into creatures of the night while trying to find out what their teacher has done with their parents.
When Sarah uses her pet bat to help show off her new cosmic copy machine to the class, something horrible goes wrong resulting in Buzz Beaker and Sarah having to save the day. Written in graphic-novel format.