A tip from our How to Do Shadow Theater forum...
Two sturdy anchor points on opposing walls or on the ceiling in your classroom will give you MANY options for securing, fabric, scenery, and even creating a theater curtain. These hooks can be used for game setups and art display too.
One simple solution is to simply thread a sturdy rope through a galvanized pipe and attach your curtain or scenery to the pipe. The pipe will eventually sag if you leave it up all the time, so keep it stored when not in use. Do not use aluminum or wood as it will sag too much.