May is hard isn't it? Would be so much easier if the weather was nice and you could just go to a park!

Anyway, I like the tea party idea. Maybe they could also decorate their own biscuits/cupcakes to take up some more time lol! Pass the parcel and musical statues/chairs is always fun.
Or Rosetti's idea is a good one, you could have a tea party and a visit from a fairy?

DD went to two parties for school friends last term and I stayed at both of them (they were both at a bistro with kids play area and kids the same age as ours obviously 5-6yrs). Most of the parents stayed, there were maybe only a few that left I think. Also on the invite they wrote something along the lines of 'please let us know if a parent is staying/leaving' which is probably what I would do just so I knew which kids had a parent present (its hard when you don't know which kids belong to which parent yet!). If you're having it at home and with a small number of kids its probably not an issue though!