Make sure you buy the discount tickets from Groupon and read the small print!
During half term you have to pay extra per person, and kids under 5 have to be accompanied by an adult so you have to buy a full price ticket for yourself to go in with them.
It's great for older kids for £6 for a couple of hours but if you have to buy a ticket for yourself to accompany a younger child and it's during half term it can get overpriced for a large indoor bouncy castle in the dark!