ScubaSteve
Wow.....what a DB
Well, I have a different reaction to the contract thing. Yes, I think the salesman you originally talked to should have brought that up and made it clear. BUT -- You arrived and you signed the piece of paper, and I think after that, you are really obligated to pay the price. If you didn't read it, that was a mistake, but not the shop's. I realize that, having arranged the class a couple of months ahead of time, you might be angry and reluctant to back out and have to wait again somewhere else, but the bottom line is that you signed the contract BEFORE you got the instruction, so I think you pay and then go elsewhere if you want to.
I agree with you TSandM. However, this is based on the assumption that this $x or $x was written into the contract. I got the impression that this was something that was presented to them after the fact. If they had it when they signed and paid, then you are 200% right. The OP is obligated. If this was not part of a document (or verbal instruction) that the OP had before signing, then the LDS is trying to change the conditions of a contract which they cannot do. I spend other people's money for a living and my favourite saying is "A bankrupt supplier is no good to me" so the logic that they need to make money is sound and true. The LDS can and should price things this way if they want.
To the OP, make sure you know when this form was introduced and what your rights or obligations are. No matter what, the relationship has gone sour so once you are done find an LDS that you respect and can do business with.