A Shrinkerscope (named in “Gets Ready, Set, Dough”) is a device inside magic vehicles, such as the Bus and the Bike. First used in The Magic School Bus Inside the Human Body, it allows the Bus/Bike and its occupants to miniaturize in size as the name implies, allowing access to otherwise inaccessible areas like human anatomies or the quantum field. Its polar opposite, the Biggifier (since “I Spy with My Animal Eyes,” previously named the Enormomometer in “Gets Ready, Set, Dough”), enlarges it instead, which is mainly used for returning to native size.
In “Ready, Set, Fail!” and “Ghost Farm,” the Bus’s Shrinkerscope makes its first physical appearance. In those episodes, it is located in the black compartment in the Bus’ roof and has the appearance of a giant laser gun (hence the “scope” part of the name). It is retractable and can also be used to shrink matter outside the Bus, much like the Scope’s portable variants. In “Flexes Its Muscles,” it is revealed to be situated in front of the Mesmerglober, the part of the Bus that controls its shape; however, the Scope being under the hood is retconned in later episodes, as it is situated in the roof hatch.
On the Magic School Bus, the size manipulators are normally activated by a combination of button inputs followed by either pressing a bigger button or pulling a lever—either the Mesmerglober handle or a different lever entirely—to “confirm” how small/big the Bus is going to become. On the Magic Motorbike, it is an add-on and is activated by button presses on the Bike’s Shrinkerscope itself. In many earlier episodes of the 1994 series, an alarm blares once the Shrinkerscope is initialized, much like the Mesmerglober, before the Bus starts shifting and deforming to enter its new size.
The Shrinkerscope and Mesmerglober often work together to transform the Bus into certain animal species, like its frog or eagle forms, hence why the two are situated next to each other within the Bus.
Activation[]
