Paper Bag to Book Cover, surface area and a tutorial

Book covers.  I like our math textbooks. They are a few years old, heavy, packed with info, and I insist that they remain covered. In fact,  I usually announce "text book cover quiz" several times each year whenever I notice the book covers becoming especially tattered or non-existent.  It's simple.  If your book is covered on the pre-announced day, you get 10/10 as a quiz grade.  My students love the idea, and see it as a great way to log an easy A as a quiz grade.  I had one very creative freshman this past year who completely forgot that I was checking book covers until he was at his locker before class.... he covered his book in his gym shorts.  "Hey, technically, it's covered, right?"  I reminded him how glad I was that he had chosen the debate team as his extra-curricular interest.  

I'm pretty tired of the stretchy fabric book covers.  They don't last.  You can't pick up the books without dropping them as they come from the lockers. Enough cracked spines.  This year, I'm having a paper bag book cover day in the first week, and I'll enfold it (pun intended) in a lesson about surface area of rectangular prisms.  I found the above picture of a drawing I did a couple of years ago showing how to cover the books.  It's a little basic.  Tonight I did some digging and found this great tutorial from the Childmade blog on how to accomplish the task.  

 So - hearty, personalized book covers,  recycling, surface area, decorating.  Sounds like a plan!

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