April 26, 2016
Ok, here is a new one! Had a super workshop yesterday in Missoula, Montana. We had never been here and just loved the people and the town! We were looking forward to a great drive from Missoula to Boise. Rental car blew up and we limped into Salmon, Idaho. Waiting for Alamo to drive a new rental car from Missoula to us as there are no rental car places here. Lessons in patience!
After being in several classrooms recently and watching students in grades 3-5 struggle with concepts of rounding numbers, it seems important to talk about why this occurs and what can be done! It often feels that the rules of rounding numbers are just procedures that are taught without recognition of the prerequisite skills required that are essential in the development of number sense.
I have long suggested a simple routine of practice that can be established in the classroom with students grades 1-5 that will ease the understanding of rounding. It all begins after students have learned the multiples of ten. I introduce the multiples of ten by playing a game called “The Roller Coaster” game. Chairs are moved to create 4 rows of 2 chairs. One student is asked to sit on the roller coaster. Students are asked, “What do you want to do on a roller coaster?” They will gleefully respond, “Whee,” and throw their hands in the air. The mathematical question is one person on the roller coaster, how many fingers in the air? This introduces the idea of _____ groups of _____ = _____ . Many of you who have been at my workshops know that this is an important visual that is a part of all the mathematical content that we teach in elementary grades.
Once students have the practice behind multiples of ten, the teacher will have each child tear a piece of adding machine tape the length of their arms from fingertip to shoulder. They will label the left with a mark for zero. (The academic name for zero is point of origin.) On the right they will make a mark and label that 100. They will bring the two marks together and crease. They will mark that with 50. The students will then put in the multiples of ten between 0-50 and 50-100. Now this tool is ready to be used with my Random Number CD 0-100. The teacher will turn on track 2. Students will hear a number and touch about where that number falls on the number line. Two to three minutes of practice is important. Students can also write the number on the number line!
Look for more helpful hints on rounding readiness soon including a new game!