Wednesday, December 14, 2011
I got the idea for this activity from two teachers, Mary Beth Runyun and Lynn Smith, who presented at the NCTM Regional Math Conference in St. Louis this fall. It is simple to do and takes little planning and gives a nice review of math vocabulary and number sense. I hung one of those big plastic candy canes full of candy that you can find at the store and put up the first clue..."Win this candy cane when you can guess this 3 digit number." I didn't make any big announcement about the activity- just waited to see if my algebra students would notice and ask questions on their own- and they did! I explained the only rule that I had for the contest was that they would only get one guess which they needed to write down on a piece of paper and turn in to me. Each day I added another clue getting more specific each day, i.e. Composite number, multiple of 5, an integer, etc. I knew they were hooked when I noticed two of my algebra students checking out the bulletin board for the next clues as soon as the bus dropped them off at school- before they were supposed to even be in the hallways in the morning! Several students had sheets with possible numbers that they would cross off each day after viewing the new clue. I have to admit I was pretty amazed. I was not sure that 8th grade students would care all that much about winning candy. Yesterday a student guessed the correct number, -645. They weren't expecting the number to be negative! Around 75% of my students had turned in a guess before the end of the contest. The best part of the activity was seeing them argue with each other about the possible solutions to the contest- using their math vocabulary.