Puzzle : Lunch Time ???

Question

A maths teacher stands in an empty room. There's no windows, and no chalkboard, no chalks, the room is completely barren except for eight students & one teacher. The students ask the teacher if they can go eat lunch, and the teacher says: That won't be necessary, it is already here., How did they get their lunch???

Answer 1

why maths teacher /??/

Answer 2

They are the lunch inside a bento box.

Answer 3

The Teacher Is Gonna Eat The Kids. Duh =]  

Answer 4

sounds a trick one, the teacher pluckes hair out of their heads

then breaking off the root of thr hair follicle making ten roots to form a shape of square, then the square root of 10 refers to " PI"

The students divided the pie and have their lunch :D

Answer 5

The teacher brought the lunch in with him/her?

Answer 6

Cannibalism?

Answer 7

cafeteria?

Answer 8

they're in a lunch box??