My children's primary school has a residential at the start of year 6 which is 4 nights at an activity centre 50'ish miles away. Today I received a letter from the school asking parents to start paying towards it (it's 11 months away) and telling us it will be £320 per child. I have twins so it's £640 for me. I'm shocked at how much it is and don't want to spend this kind of money on a school trip. AIBU? What would you do?