Image that represents a concept in the book, "Why Don't Students Like School"

People enjoy mental activity under certain conditions, but if a student believes that an activity is to difficult or too easy, they are quick to check out, lose interest, and stop listening. This picture I found in Flickr brought a smile to my face. I've seen this look on a student's face before! I might as well been talking to a skeleton. Time to change the delivery method!