Just a thought for the awesome playground you're making for our school! How to Make an Outdoor Chalkboard- What a fun outdoor activity for the kids! Full tutorial includes list of weather proof materials!
how to prevent outdoor chalkboard from rotting How to Prevent Your Outdoor Chalkboard from Rotting - make my own using exterior paint & unsanded tile grout -- 1 cup exterior paint mixed with 2 tablespoons tile grout.
Beautiful DIY Pallet Projects - How Pallets Aren't Just Used For Shipping Anymore