Besides adding excitement to my classroom, the puzzle presents the students with a mental challenge unlike most of their other intellectual endeavors. So much of what is taught at school is initially unknown to the student; however, the best feature of these puzzles is that the intent of many of them isn't to teach something new, but to make the reader think differently about something that is obvious. Week after week many of my students slap their foreheads on Fridays and proclaim, "Of course!" But, as the year has gone by, I have seen a marked increase in the number of correct responses!