A classroom with Baldi's Math Machine and some number balloons.
Classrooms are rooms placed around the Schoolhouse and Super Schoolhouse. Every classroom has a teacher's desk, blue carpet flooring, a chalkboard with something written on it, possible items on some of the tables, possible papers and an uncollectible notebook objects, and a collectible notebook on the big desk the player can collect. All classrooms have at least one class door with the number 99 on them and some classrooms can have more than one door. Since floor 2, some classrooms contain number balloons and Baldi's Math Machine, which the player needs to answer the problem right to make a notebook appear.
Overview
Main gameplay
General
A different amount of classrooms can generate depending on the floor:
Occasionally, the player will be chased into a room by Baldi but may escape by mimicking the opposite of his movement path, effectively running around him to escape. This will set the player in close quarters with Baldi for a time, making them vulnerable until breaking out of his range of chase. Another way to escape this situation is answering the math problem correctly on Baldi's Math Machine if the classroom has one, which results in Baldi being delighted for five seconds, allowing the player to escape easily.
Principal of the Thing will occasionally survey classrooms on patrol for suspicious activity, however, he will not pose a threat to the player unless they are breaking the school rules.
It's a Bully will sometimes block a classroom from being entered, depending on the chunk of any hallway he is on.
Chalkles will spawn in any classroom, slowly starting from the chalkboard. Once Chalkles becomes fully solid, he will fly out of the chalkboard, laughing to get Baldi's attention and locking the door(s) for a few seconds.
Mrs. Pomp will invite the player to a random classroom once she spots them. The map shows her classroom until the player enters the room or the timer runs out.
Some classrooms can also contain two doors which can lead to hallways, another classroom, or other locations.
Rarely in floor 2 and 3, small classrooms will be generated and they do not contain any items or furniture.
This is a list for all defaulted rooms. In Hide-and-Seek, Explorer Mode, Endless Mode - Random, each classroom comes with random strings of items and objects.
Every classroom has roughly 8-10 desks facing one wider desk (assumed to be the tables and big desks, likewise). They are arranged differently in different rooms, and one even has them all flipped over.
Principal of the Thing and Mrs. Pomp are the only characters that can enter classrooms while passive.
According to mystman12's Twitter, if the player is extremely unlucky, Baldi can wander into a classroom even when WD-NoSquee is used.[1]
A tiny classroom.
Rarely, a tiny classroom would be generated.
Classic/Birthday Bash
The "Geology" classroom has way more desks than the other classrooms.
Baldi's Basics Classic
Prior to V1.3, the Safety Scissors items are absent.
Before V1.3.1, Playtime could also be passive while entering, but this was changed.
In older versions prior to 1.4.3, the Big Ol' Boots is not found in the "History" classroom as the Big Ol' Boots were not implented yet in this game.
Glitches
Baldi's Basics Birthday Bash
There is a glitch where NPCs cannot enter the "Geology" classroom.
A classroom in one of Challenges Demo's screenshots.
References
↑"Baldi really does only know where you are based on audio, or of course if he sees you. The WD-NoSquee item allows you to hide in rooms because Baldi won't hear you go in. (If you're *super* unlucky, he might randomly wander in). You also can't let him see you enter." - mystman12. June 4, 2018. Twitter
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