Love the idea as well. Always need a spot to leave a message or a reminder to do something.
We have been suggesting to folks to use the spring wing toggle bolts or the Moly bolts for anchors for hanging things that have weight to them. The 1/4-inch thick walls dont offer much weight handling. This chalkboard/corkboard might not be to heavy to require something like this and just sticky tape or velcro might work just fine . If you are worried about it being too heavy then try this idea. The MOLY bolts probably would be the best choice.
photos from google images