"Going Batty" is the fourth episode of season two and the seventeenth episode overall of the animated children's series The Magic School Bus. It originally aired on September 30th, 1995.
The class is studying nocturnal animals at school and eventually checks out the attic of the classroom. Inside the attic, Tim notices a bat hanging from the ceiling and confirm that the bat is the only nocturnal creature they know very little about. Just then, the bat flies away and Ms. Frizzle suddenly appears, dressed as a bat. She tells the class that she will "show them the secrets of being nocturnal". As Ms. Frizzle tells the class more about the night, Ralphie becomes apprehensive.
The students' parents arrive at the school, and Ms. Frizzle, after being introduced to Keesha's grandmother, tells her that she could just "eat you up", exacerbating Ralphie's trepidation. When Ralphie's mother Dr. Tennelli meets Ms. Frizzle, the latter states that, "I do so enjoy taking him under my wing", which finally convinces Ralphie that Ms. Frizzle is a vampire as he tells the rest of the class. He uses Ms. Frizzle's term "The darker the night, the safer the flight" as evidence to support this, but Dorothy Ann states that Ms. Frizzle was talking about bats, for when it's dark, they blend in and are unobtrusive to enemies. Ralphie, however, is not convinced as he states that vampires come out in the night to. The conversation is interrupted when the class overhears Ms. Frizzle informing the parents that the class and their parents will go someplace more "suitable" and "breathtaking" right before letting out a sinister laugh. As the parents enter the bus, Ms. Frizzle tells them that the children "will be taking care of" and takes them on a nighttime field trip to learn more about bats. The class follow her and their parents via 8-seat bat mobile driven by Liz to a scary old castle.
As they arrive at the castle, they spy on Ms. Frizzle and their parents, who enter the castle. When Ralphie keeps trying to convince the class that Ms. Frizzle is a vampire, Keesha, having enough of this, decides to see for herself and the class walks to the castle. Wanda tries to open the door. But the handles break apart. When Ralphie views Ms. Frizzle and the class' parents drinking a beverage each through the window, he becomes convinced that Ms. Frizzle is making the adults drink blood.
Keesha tells Ralphie that the adults are drinking tomato juice, which Ms. Frizzle served at the class picnic. Ralphie then comes with a plan to drive a textbook in the heart of who he calls the "teacher vampire". When Carlos swats mosquitos off of him, the bats fly around the class, and Phoebe tells the class that the bats are really eating the mosquitos, causing Keesha to come to the conclusion that the bats aren't vampires.
Meanwhile, Ms. Frizzle gives the adults a tour through the inside of the castle and they walk around "bat guano", the waste of the bats that makes great fertilizer according to Ms. Frizzle. When they walk through a stuffy hallway, Ms. Frizzle tells the adults that it's from the breath of the bats, and Mr. Ramon jokingly states that "bat breath is better than no breath at all". They then come across pink bat progeny, which Ms. Frizzle calls "the children of the night".
The class also views them through the window and Keesha informs Ralphie that the bat babies drink milk and not blood. Ms. Frizzle tells Keesha's grandmother (who has heard Keesha's voice from outside) about how bats protect their young and Ralphie is convinced that Ms. Frizzle will feed the class to the bats, misconstruing tidbits (food fed to bats) as "kid bits". So he brings the class with him to get help.
When they enter the bus, Ralphie tries to drive it so the class can get out of here before Ms. Frizzle catches them. He pushes the bat button and the bus transforms into a bat, which flies through the woods. The class are impressed of the fact that the bat-transformed bus isn't running into any trees. They notices that as the bat-transformed bus makes the pinging sound, it opens its mouth and wiggle its ear to listen to the echo of each ping. Keesha finally infers that when the sound the bats make echo back, they know something is there and avoids crashing into it, as they use their echoes to locate things. They also learn that bats see more with their ears rather than just their eyes. When the bat-transformed bus eats moths, the class also learn that bats are at night to find food in the dark. Ralphie presses another button on the bus, which transforms him and the rest of the class into bats. Just then, they come across an owl, who attempts to catch them, only to miss in the process. The students then learn that the bats' enemies can't see them due to the dark.
When the students overhear a vociferous Ms. Frizzle stating, "At last, the moment I've been waiting for has come", Ralphie tells the class that the vampire in his comic book said the same thing and the class fly to the castle, with Keesha reluctantly starting to believe Ralphie's theory. They hear Ms. Frizzle asking who would be her first victim, and Keesha, after overhearing her grandmother telling Ms. Frizzle to take her, flies inside the castle.
The rest of the class follow along and use their sound to locate Ms. Frizzle and the other adults. They come across more bats and finally hear the adults voicing their opinion of the field trip to Ms. Frizzle, as Keesha's grandmother tells the teacher, "I can't believe I let you do this to me" and Dr. Tennelli states that, "My neck will be sore for a week". Ralphie brings the class with him to fly to Ms. Frizzle's location as Mr. Perlstein is heard saying, "Maybe we should've stayed home tonight".
The class finally spot Ms. Frizzle and the rest of the adults hanging from a chandelier dressed in bat costumes. The class fly through them and the adults extricate themselves off the chandelier. When the class finally find the truth, they all chide Ralphie for his theory. Ralphie apologizes to them and acknowledges the fact that bats aren't vampires, but nocturnal creatures that come out at night to feed on insects. Carlos jokingly states that "The bat news is we're still bats". Liz comes around with the bus and the class hops inside to transform to their human form just in time for their parents to exit the castle. When Dr. Tennelli asks Ralphie what was going on, Ms. Frizzle states that he and the rest of the class were just "hanging around", with Ralphie stating "bats all" as he and Ms. Frizzle laugh.
- This is the first time the students changed into animals as well as the bus.
- Carlos, Keesha, and Arnold's last names are revealed in this episode.
- Guest Stars: