Pretty much finished this now in the garden. It used to be a heavilly planted shrub bed, then I cleared it and turned it into an allotment. Then with the second child due any day now, thought I'd make a proper place for them to play, (I also get my garden back and more space in the workshop, I hope!)
So we now have a new club house with fitted carpet, big desk and chairs, with plans for the outside to have a long shelf covered with a lean to tarp, for a sand and water bucket area. It leads to to weeping willow, tree house and chicken run. Best thing is apart from the swing and trampoline and some time, it didn't cost anything. A few skip dives, other folks rubbish, some foraging and left over materials from jobs in the past.
Mind, I ache a bit now, just some painting to finish, a fence to make out of split hazel when I get some more coppiced material, and the lean to.