If you have a child that is 3 or older this tip is for you. This was hands down the best gift I could have given Brooklyn and it only cost $3.87 at Walmart. They are Washable Window Markers by Crayola.
This has kept her busy for days. We even took them to Indiana with us and she made grandma's windows very pretty and colorful. They literally wipe off with your finger. I love it because we're not going through a ton of paper so it's earth friendly too.