Haven't tried it myself, but it's a pretty solid idea, which I might bank and steal for later.
My daughter's dance studio offers something like this at intermittent times of the year. Understanding that it is glorified baby-sitting is the first step, as for these events, the 'baby-sitting'/dance event allowed siblings to be dropped off as well as the dancing student. This meant, for the dance studio, that quite a few of the participants really didn't want to participate.
Make sure you have insurance. Make sure all parents sign a waiver for every child/provide insurance details, just to CYA. Make food/snacks a part of it.
Be prepared that it may become a drop-in session for some unless you're very clear that there is a definite set start and end time. That would be up to you. If it is to be a drop-in, any time kind of a deal, make it clear on paperwork that the cost is a flat fee that isn't pro-rated (i.e. you pay $25 whether your kid stays an hour or four hours). Something to consider, at least.
I would say use fairly universal activities that all kids can succeed in. Avoid competitive games, as you may well receive students who have no ability to lose graciously and will have a fantastic super melt-down when they lose a game. Or be prepared for it, one of the two. At the dance studio, they did a great job of creating a schedule of activities that were suitable for all (non-dancers as well as dancers). Theatre might be 'easier' than dance, as its a different skill set, but choose the activities wisely.
It might even be worth having a couple of stations. There will be, despite your absolute best efforts, a couple of kids who cannot/will not. Having a quiet corner for them to read or be by themselves is a wise option. Ban electronic devices, and they will probably get bored of being by themselves after a while and join in. But it's good to have this as an option, as long as they don't have a screen they can tune the rest of the world out with.
In order to pull in as much money as possible, you might want to consider running a couple of these events in the lead up to Christmas, in order to give parents ample time to go shopping. Maybe even a special 'Black Friday' event...though that might be a little more tricky to swing, it'll depend on your community and administration.
These are just some spit-balling ideas, based on observations and thoughts. Good luck!
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Phillip Goodchild
Theatre Arts Instructor
Etobicoke ON
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