"On the first night of The Nutcracker, my mum was more nervous than I was," remembers Julie. "My mum was crying," says Ashley Paterson from Barrhead, who played the part of Clara, the little girl whose dream forms most of the action of the ballet.
Their friends may complain that they can't come out to the cinema, and the boys at school may think it "a load of malarkey", but they are sanguine. "We've got the weekends for cinemas," says Sarah with admirable maturity.
Another girl in the changing room has a professional dancer for a sister. "She tells her what it's like; the bad things like having sore feet every day. " Doesn't that put Sarah off? "No, I think having sore feet every day is what tells you you're a ballet dancer."