How about a return to the classics for a summer reading pastime? The library has a display of suggestions from old standbys to more modern selections. Get a laugh from Mark Twain's Life on the Mississippi, shed a tear reading A Tree Grows in Brooklyn, get outraged from Upton Sinclair's OIL! or scare yourself silly with Dr. Jeckyll and Mr. Hyde.
There's also a handout of "The 10 most re-read books" as suggested by the American Library Association: Harry Potter and Charles Dickens both make that list. On the younger side are the Little House on the Prairie series and Winnie the Pooh. Shakespeare is included, and few more suprises.