I love this idea. I would do it, get removable wall paper. - "A neighbour of mine has one wall in their house papered like this. Every time a new guest comes in, they are asked to colour-in a character and initial it.
If you want to update the look of your bedroom, but don't want to spend a load of money on redecorating and brand new furniture, the DIY Book Headboard is a fun and inexpensive way to change things up. The DIY Book Headboard is a fun decoration project.