The Problem with Great Expectations: Should kids be pushed to read more difficult books?

A parent of one of our middle school students approached me at my daughter's ballet class a while back.

“I was hoping I might be able to talk to you about my son,” he said, shaking his head and wringing his hands in a way that led me to believe the young man must be a drug addict or serial shoplifter.  “He’s constantly reading graphic novels.  What should I do?” 

The idea that parents ought to “do something” when kids aren’t reading the books that fit our notion of what t...