Any particular reason why the OP feels she needs to foot the entire bill?
I have learned that people tend to value things more if they have some "interest" in them.
They paid something for whatever - contributed time/effort to the project -
Perhaps the girls (or their parents) that are interested could do a fundraiser for themselves? or ask around? or even contribute a token amount to the project?
Sometimes when something is "just handed to" someone - the someone does not take very good care of the item.