It would be fun if the Library had a spot for when you complete questlines that it has everything written like a story book. Sometimes it is so far between finishing quests I forget what happened before. I know you can go back in your quest log and read them but it would be nice if they were all in one place as a giant wall of text or something.
You could even add it to the school house. Be like a history lesson since in some cases one could argue you are making history or atleast a big mark on the town. It would be fun to have the entire retelling of the tale in one place and then have a little quiz after for some small rewards.
There could also be a badge made for like honors student or something. Not make the quizzes needed for quests like some of the quizzes but just have it as a fun little side thing and then make a badge to encourage people to do it. You could even keep the prizes very small from the quiz and then make the big prize when you earn the badge