Going to the media center next week with a K-2 class? If so, right before you go, you should read Ian Schoenherr's Read It, Don't Eat It. This is a fun book of dos and don'ts for book etiquette. Told in rhyme (Borrow, don't steal. Try not to squeal.) with humor and colorful illustrations, Read It, Don't Eat It will be a crowdpleaser and your media specialist will love you for reading it.
Thinking beyond the application for the media center, this would be a great starting point for creating other lists for different places in your school. Play It, Don't Say It could be a list for behavior in the gym. Color, Don't Blubber might work for the art room. You get the picture. Read It, Don't Eat It could also serve as an introduction to the concept of contrast with the good and not so good behaviors.
Check out Ian's blog to see some wonderful illustrations.