Have some Halloween fun with the witch’s tale Room on the Broom. In this lively story by Julia Donaldson and Axel Scheffler, a witch makes room for her animal friends to ride on her broomstick… until there’s one too many animals, and the broom snaps in two. Then, when a hungry dragon threatens, the animals use their wits to save the stranded witch. The central question of this book – Is there room on the broom for me? – is a mathematical one. It is a good opportunity to introduce Room on the Broom activities.
The answer to the question is subject to the constraint of how much weight the broomstick can hold. Identifying the constraints in a mathematical situation is necessary for making sense of the problem and for reasoning about possible solutions. One teacher developed a mathematical task for first grade by assigning weights to the different animals and giving the broomstick a weight capacity of 13 pounds. The task:
Show any combination of animals that weighs 13 pounds––no more and no less!
The teacher selected the number 13 as the constraint because she knows that first graders are working to develop fluency with sums to 10. They are also working to deepen place value understanding of teen numbers as a combination of a ten and some additional ones. She anticipated that students would use the familiar strategy of “make a ten” and then add three more. So the numbers she chose to assign to the different animals’ weights lend themselves to this strategy. (Dog=6 lbs., Cat=5 lbs., Bird=2 lbs., Frog=1 lb.).
This task, with many possible solutions (see student work), generated more mathematical talk than the teacher even expected. One boy became interested in the smallest number of animals required to reach 13 pounds (3) and the largest number (13). The ensuing debate over whether or not there really would be room for all these animals on a single broomstick lead to the question of another constraint: the length of the broom!
You can design your own task, with numbers appropriate for your class, by downloading the master we have available here. The images are from www.roomonthebroom.com, where you can also find more book-related activities. We invite you to tell us about your own experiences using Room on the Broom below. Don’t forget to let us know the grade you teach and how you tailored this task to fit your students.