We just did silly stuff for DS's last year. Run round the circle like a chicken with it's bottom on fire proved popular. Do an impression of a rock star. Pretend to be a firework. They all worked well, there was only one boy not keen but one of the others said he'd do it and then they were all doing it (inc the boy he wasn't keen). I think it worked really well, and I normally hate pass the parcel!
Pretend to be a boy (all girl party) Run outside and shout "I'm a ..... Idiot / fool / silly banana etc) Tell a joke Make the biggest fart noise you can (they found that hysterical!) Tell us an embarrassing story Dance like your dad Dance gangnam style Pretend to be a chicken laying an egg