If the rooms and hall are all connected so you dont have to clean equipment to move to the next area then I would charge around $0.40 to $0.55 per sq ft
If the rooms were all over the school and you had to keep cleaning off the equipment and moving everything to different places of the school charge a little more for the time and trouble.
A lot depends on how sure you are that you can land this job as some people would bid this as low as $0.20 sq ft or around $632.00
I would say $1500.00 would be our low on a job like that