Also on these boards
Outdoor Chalkboard - MDO plywood -Medium Density Overlay - it's a weather-resistant plywood that has a smooth surface. One coat of primer (front & back) and three coats of chalkboard paint on the front. Mount to the fence with 6 screws - three on the right and three on the left.
Outdoor Chalkboard. Birch plywood, painted front and back with primer to seal it, and then we just painted the front with a quart of chalkboard paint. Attached to the fence with galvanized wood screws. So far so good, it's been 9 months and it looks brand new.