In a very round about way, I discovered the Flickr pages of a man who draws on his children's lunch sandwich bags and has done so since 2008. His name is David LaFerriere. His drawings are all whimsical and super creative. Wish I thought of that.
Here's a video of his explanation for what he does.
Thanks to Betsy at Fuse#8 and Crooked House for sharing this.
Happy Dad's Day to all the Dads out there. You don't need to do artwork on your kids' food to be a super Dad.