This is a great project idea for homeschoolers. Perhaps you would need to have multisig so the parent(s) must approve the posts also. It would be the end of kids not wanting to do homework.

You could also make field trips into geocaching games. Museums, and other science education type venues. For learning to do farm work, there could be tasks like quests and rewards for tasks completed.

In fact, it isn't hard to see how this could translate to an organisational structure for a business too.