I recently had a friend in North Carolina asking me for some inspirational photos for creating a room for her two three year old girls. She was interested in creating built-in beds because although the girls were begging to share a room, she still wanted them to have a little privacy as needed.
Well I found this room designed by Ginger Brewton Interiors and thought it wonderfully captured all of her needs. It offers separate closet space, full beds which can offer privacy with curtains, and a few feet of play space in the center of the room. (Obviously for two little ones I'd replace the chairs with a play table).
As long as the room that you are working with is big enough, this is a pretty easy project and only entails a little framing and drywall. Luckily she is building a house now so has the ability to create whatever she wants with her architects.