To begin this lesson, I give each child a massive pile of buttons to sort. I have found some scrap stores near me that charge a small fee to load an entire grocery bag of items such as buttons. Typically I will start a lesson together on the carpet. However, for this lesson I do not want the children getting any ideas on how to sort the buttons from me or the picture book. I tell the kids to immediately begin sorting the buttons as they see fit.
Here are some examples of student sorts :
Students are asked to explain their method of sorting to me as I walk around, or to a neighbor. It is important for students to explain their thinking. Students need to construct a viable argument and be capable of explaining why they sorted a particular way. This skill falls under mathematical practice number three. A students' understanding or lack of understanding is evident when they are asked to explain their thinking.
I have included a student video talking about her specific sort.
After sorting our buttons, we meet on the carpet. I read the book, The Button Box by Margarette S. Reid.
This book describes in detail many attributes that could be used to sort buttons. As a class, we discuss the different ways they chose to sort the buttons compared to the ways we heard about in the story. While we are comparing and contrasting our sort vs. the sorting in the story, I am able to listen to students thoughts and the vocabulary they are using.
This is reinforcement of the mathematical practice being targeted: constructing and explaining a viable argument. Reading the story also gives my students new ways to think about sorting that maybe they had not thought of while they were sorting the buttons.