I think you're about to be buried under a mountain of "tables" :smileywink:
1 table for list all schools (1 record = 1 school)
1 Table for listing all rooms (1 record = 1 room from 1 school)
1 table for listing all equipment (1 record = 1 piece of equipment)
Set up relationships:
Schools::SchoolID = Rooms::SchoolID
Rooms::RoomID = Equipment::RoomID
You may have equipment with very different features/information that you want to record in your inventory. If so, you can either define additional tables for each type of equipment or simply define a lot of fields in your equipment table and use just a subset of the defined fields for each piece of equipment.