Make your own DIY overhead projector for tracing wall murals. Make a makeshift projector using a box, a lamp and some tape. Project the transparency onto the wall. Use a light bulb without the "frosting" on the inside for a clearer picture.
She wrote an entire chapter from the Harry Potter book on a wall in her cupboard under the stairs. That's dedication! Would be a fun idea to write a whole Dr Seuss book on a wall for a kid's room though. Me- I love the writing look on walls