There are some great resources on the GirlGuiding UK website, including some amusing games. (I know they are designed for Guides, and as a Leader, I'm rather older than the target audience, but it doesn't stop me having fun!)
My favourite one at the moment is "I'm a Camp Leader, Get Me Out Of Here", which allows you to run a virtual Camp! There's a whole page of games here and also some of the same, and some different ones on the Senior Section site.
As we're coming up to that time of year that's full of revision and exams, it's always nice to have a little distraction for 5 minutes to give our minds a break.