Creating a guest room
If you have a spare room in your house, you may not know what to do with it. Often if the room has no defined purpose it just becomes a dumping ground and gets full of clutter and junk. If you do not have a place that guests can stay when they come over then why not make it in to a guests room.
Often it is the smaller box room that is left unoccupied in the home, and this may not be big enough for a double bed. You may ne able to get a sofa bed that will fit once it is pulled out and allows for a bit more room when it is folded up. Try and use the space effectively and add wall cupboards and shelving to allow for more floor space.
If the room is not suitable for a guest room or is not needed then how about making it in to an office or even a gaming room. Having a desk where anyone from the family can go and work is a great idea and can mean that they get much more done. Having a gaming room will allow you or your child to have a few games on the computer or console without taking over the main television.