I have several head boards and air mattresses in my staging arsenal. I don't typically stage kids bedrooms, but the master is one room that needs to be staged. Staging gives people of sense of how furniture works in the room, and how much of their furniture is going to fit. It also defines the space, sometimes it's not always easy to tell which room is the master.
I usually start with the bed. I will prop up the headboard against the wall and start inflating the air mattress.
I then take duct tape and make pleats as I'm taping the fabric to create a bed skirt... It's surprisingly easy to do!
A nice white coverlet always looks fresh and clean, and matches any room decor!
Matching bed side lamps are a must! I don't love matching things all the time, but in the bedroom I think a pair of matching lamps pull it all together.