Q: What is the restroom at school called?

Is it the boys' room or the girls' room?
Is it the staff's room for teachers?

the boys' restroom

the boys' lavatory

the girls' restroom
the girls' lavatory

the faculty restroom
the staff restroom
the staff's restroom

If anyone thinks of others, I'm sure he/she will add them!

The restroom at school is commonly referred to as the "boys' room" or the "girls' room" for students. These terms are used to indicate the gender-specific facilities. However, schools may also have a separate restroom designated for staff or teachers, known as the "staff room." This is typically a private area for staff members to use during the school day. To provide a more specific answer, it would be helpful to know the context of the question, such as which specific type of restroom you are referring to.