Using foam board is a great way to introduce children to the concept of printing. I usually get the children to start with an abstract design, to get them used to drawing marks into the foam board. It is not as easy as it looks, so something abstract looks a little better. A normal, sharp drawing pencil is often the best way to make impressions into the foam board. Make sure they do not go all the way through. Once this is done it is a simple case of showing the children how to use inks - rolling them out in pallets, making sure they have an even covering and keeping some rollers clean for dry rolling. Enjoy!