R.O.
I tried the something similar to what Kim did (use magnetic paint as a base coat) & what Heather suggested (dry erase paint). Mine was a flop, by the time I put enough coats of dry erase paint on, the magnetic paint didn't work anymore. The magnetic paint was expensive and very weak to start with. The dry erase paint never completely erased, color got trapped in the dimples left by the roller. So I tried using a foam roller and it was a little better but still never completely erased. We ended up using bath tub crayons on it because a damp paper towel took all the color off. We also tried to use the dry erase board they sell at the hardware store with similar results. I think it is a great idea, but suggest asking some of the moms that have had success what brands they used. I used stuff from Michaels craft store (sorry I can't remember the brand).