I've been dying to try styrofoam printing with Starboy for ages. I got the idea from The Artful Parent. The results are fantastic!
That laundry mountain in the background? We're ignoring that. We have priorities.
I did make a drawing of a truck on the fly, and when he discovered that new images could be made on the fly, he started to demand more trucks, wanting to make only one print of each one. For your first attempt at this, it might be a good idea to pre-make the printing "blocks" and keep it at that, unless you have all day to spend!
This project was lots of fun, and really satisfying. I enjoyed it, too! If you have older kids, this would be a great idea for a Valentine's Card-Making after-school gathering.