The first day back to school after NCSM/NCTM is definitely an exciting one! I was excited to see my students, hear and see them doing math again, and incorporate the amazing things I learned at the conference with them. It is always great when I can go to a session, regardless of the grade level focus, and be curious how my students would engage in the activity. For example, I went to an amazing session on counting by Kassia (kassiaowedekind), Elham (@ekazemi) and Allison (@allisonhintz124). While the session focused on whole numbers, I began thinking about how I could take this same practice of Choral Counting and use it in my classroom. I have to admit, while my first thought was what my students would think about during this activity, I also had my own curiosities in the teacher organization of the work. Does writing them horizontally vs vertically bring out different noticings or patterns? or How does how many I put in each row or column affect their thinking about it?
Luckily, we are currently working on multiplication of decimals and I thought this would fit in just perfectly. I did some brainstorming and decided for my first class we were going to choral count by 0.3, record horizontally and vertically and have 1/2 of the class focus on the horizontal while the other 1/2 focused on the vertical. I was curious to see if they saw different patterns emerge. I started at 1.5 because I wanted a number that would hit a whole a couple times in our round but not make the “10” of them makes a whole number so obvious.
Here are a few students who used the vertical recording…
Here are some examples of horizontal, again, many of the same patterns…
I asked one student, who seemed content with his noticings before they shared as a table if he could think of any equations that matched the number patterns he saw while he waited.
I asked him where he saw the last one in the numbers and had him record it in Educreations: https://www.educreations.com/lesson/view/multiplication-decimals/31049585/
When the second class came in, I decided to switch up the number in each row to five (thanks Elham for that suggestion) to see if differences came out. Here was our board:
i definitely like the 5 in each row better than the 6, a lot more patterns emerged, quickly. It pretty much screamed patterns! We shared them all and I asked each table to pick one they wanted to explore deeper and figure out why it was happening.
This student said, “If you pick any number, go up and then over two the tenths digit will be one more than the starting number. It also works if you go down and then over two.” He explored that one here:
It was a wonderful first day back! My students and I really enjoyed the choral count (although they all spelled it coral:)! It was a very safe feeling knowing they were all saying it together, a bit different than the counting around the class.