You've got some options, but I would want to know:
A) Was this made clear from the outset? If they told you about it, and have never hidden the fact from you, then what is the problem you have?
B) Was it in the contract you signed when you handed over the deposit?
If this has been sprung on you, then I would be suspicious, refuse to pay anymore, and ask for the money back. If you pay by a credit card, you can be protected from a school going bankrupt.
However, I would suggest you phone up the school and ask to speak to someone who is authorised to deal with this sort of query. The email you received might be from some young spotty oik who, first isn't authorised, and second, doesn't know what they are talking about.
If the school is reasonable, they will listen to your concerns, and come to a compromise. If not, then that tells you all you need to know. But, in my experience problems and issues are best sorted out by personal intervention, rather than emails. So, get your requests sorted out before you phone, know what you want, and be ready to offer a solution when you speak to whoever. They will probably listen.
Good Luck
