Open Question: what are some good things to do while camping out in the back garden?

our back garden is not very big, it's just big enough to fit a 2-roomed huge tent on the grass.
im thinking of having about 3 of my friends around, all girls, aged 12,13&14.
what are some cool things we could do in there?
it's going to be very hot, so it may get over heated.
if we use face masques they may turn to concrete and stay in there forever...:L
yeah we'll be taking pictures!xxx

Source:
http://answers.yahoo.com/question/index?qid=20110727070214AAKpXf8

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