## Making Sense of Mental Math – Number Talks

“All students can learn mathematics and deserve the opportunity to do so.” -The Ontario Curriculum, Mathematics Grade 1-8

When I ask you to answer the math problem 5 + 7, I’m sure that most of you could come up with the answer of 12 pretty quickly. But, if I asked you to explain the process or steps that you used to get to the final answer of 12, it might take you a bit more time to think about it. This same thing happens when we ask students math questions. They are often able to give us an answer, but when we ask them to explain their answer, describe a strategy that they used, or even just write out their answer step by step, we can be left with something in between a blank stare and a beyond puzzled expression. Although our students may be able to give us a correct answer on a test or worksheet, we may have no idea what process they are going through to get that answer. The same goes for a wrong answer. If a child gives a wrong answer, but we can’t seem to figure out where they veered off course, we won’t be able to guide them back onto the path to success.

During my most recent school placement, my school ran a professional development day on a new classroom tool called “Number Talks.” Some of you may have heard of the concept, developed by Sherry Parrish, but to me this was brand new. The main purpose of a number talk is to dissect a mental math problem with your students, and discuss and evaluate the different strategies that can be taken to solve that problem.

For example, I used a number talk with my Grade 4 students when discussing how to show a specific time on an analog clock. Students were tasked with telling me how they would show 7:35. I emphasized to them that they not only had to give me the right answer, but if they wanted to respond they would also have to tell me *how they knew* where to put the hands on the clock.

The Number Talk incorporates another great strategy that can be used not only during these discussions but also as a general classroom management strategy. When students are thinking of their answers, they are not to put their hand up or shout out any answers. Instead, they hold a fist on their chest, and if they can find one way to answer the problem, they simply stick their thumb up. If they find a second way that they can solve the problem, they stick up another finger, and so on. This way, the teacher is able to assess students’ understanding, but other students are not distracted (or discouraged) by their peers’ progress.

After students were given ample time to figure out their answers, we took time to hear different strategies of knowing where the hands should go on the clock to show 7:35, some including counting by 5’s, going straight to 7:30 and adding 5 etc. We listened to all of the different methods that students had used, discussed their effectiveness (eg. counting by 1’s to get to 35 was not found to be very effective by my students!) and talked about which strategies different students preferred to use.

I have to say that as someone who grew up simply memorizing math times tables and addition facts, this was a wonderful concept to be introduced to. I found them to be extremely effective as a “Mind’s On” activity and to get students thinking about how math operations and concepts really work. Although math is generally a subject that allows for very little deviation, this activity shows students that there are often ample strategies that they can use to solve math problems. Number Talks give them that bank of strategies to use for math problems, and it also allows teachers to learn what is really going on in the minds of our students, even if we are asking them “simple’ questions like 5 + 7.

There are some great resources out there for teachers interested in incorporating Number Talks into their classroom. This article written by the Parrish gives a short and simple introduction into the concept and even walks through an example with student dialogue and diagrams.

For further learning, you might want to consider buying Sherry Parrish’s book “Number Talks Common Core Edition, Grades K-5: Helping Children Build Mental Math and Computation Strategies.” Youtube is also a great resource to see some real Number Talks in action. Here is a favourite of mine, but just by searching “Number Talk” you will be able to find many more.

Do you use Number Talks in your classroom? Do you think this is a useful strategy to help kids delve deeper into math comprehension? What are some other strategies you could use to help understand students’ mental math processes better? Let us know what you think below!

*Allison Dyjach is a Faculty of Education student at Queen’s University in Kingston, Ontario. Connect with her on Twitter @AllisonDyjach, or follow more of her Bachelor of Education experiences on Instagram @allisondyjach. *