I built a play house and swing set for Bailey (and Caiden, even though he may be growing too old for these things). I drew up the plans myself. It's not quite done (still need to paint, add some paneling inside to cover the bare studs, paint, and get some furniture for the inside), but it's usable. I'm also probably going to re-do the ramp leading up to the deck.
Started off by measuring out placement for the posts
Cemented in the post holders and mounted the posts and joists
Started adding the sub floor
Added some cross bracing on the bottom so Bailey could dance on the top
Framing (note, for all of you contractors out there, I realize this is not to building code :-), no king plates or proper framing for windows and door ways, but this is just a playhouse).
Roof going on (I've never built my own pitched roof before)
Added T1-11 to the front and decided to just eventually paint over the OSB on the other sides. Also added cedar to the framing and made a fancy front door
Made sky lights on each side before I roofed it and covered the wood with galvanized metal
Started making the swing set (note the door I added to the play house in the background and the shutters)
Bailey loves her play house
Side note: My neighbor is building a TALL playhouse behind us. We both started building at the same time (almost on the same day) without knowing what each of us were up to. We eventually started to help each other out. His has some SERIOUS creativity (he built that slide out of 50 gallon drums). He's still working on it (this picture shows it without the stairs or railing), but he's worked his tail off on this one.