Here are the job levels and descriptions:
Janitor At The Library
It's your job to keep the library clean. You will be scrubbing toilets, sweeping and mopping floors, and dusting off old books. You need to advance your cleaning skills in order to move up to the next level.
Keep both eyes open for anyone causing a ruckus in the library. Sure there are people who just want to come to the library who just want to study or read, but there are plenty of people out there who would stir up an uproar in the library.
You will be stocking books, helping patrons with whatever they need, and working with the librarian doing things like reading to children, and teaching computer classes.
Here is an example of a chance card question:
Here is the custom icon (Enlarged)