I am preparing to switch up my kids' rooms.  By this I mean that I will have two girls in one room and our son in another.  Any great ideas for the girls' room especially?  It is not super huge, so I need to utilize my space as best as possible.  They are still small (ages 4 and 2).  I would like to do something that they won't grow out of right away.  I am just looking for something original, affordable, and not too time consuming to do as I need to pull this off in one weekend.