## Which One Doesn’t Belong (again)

This is a good week.

No.This is a GREAT week.

A colleague and I have the privilege of spending four days with four groups of teachers: Day 1 with TK and Kindergarten, Day 2 with grades 1 and 2, Day 3 with grades 3, 4, and 5, and Day 4 with MS math teachers (grades 6 – 8). Pretty nice.

The opening task of each day is *Which One Doesn’t Belong? *It’s a pretty nice way to start the day. We show a photo, similar to this one we used with grades 1 and 2.

We ask everyone to take a moment to think about and prepare a response to the following questions:

- Which domino doesn’t belong? Why?
- Find a second or third reason why the domino doesn’t belong?
- Find a reason why each of the dominoes would not belong.

Then, everyone has the opportunity to share their ideas in small groups. After a bit, the entire group chats about the reasons why each domino does not belong.

Some more good stuff happens as teachers make their own WODB that can they use next week–which for us in this part of Southern California–is the FIRST week of school. The conversations really gets going: ideas are shared, drawing, planning, arguing, advocating for ideas. Pretty nice.

We do a Gallery Walk. After, the groups retrieve their posters, review the reasons that were noted on their posters, and make any revisions they want to based on the feedback shared during the gallery walk.

**The best part happens now**. We talk about how *Which One Doesn’t Belong?* is good for kids. We talk about how this is a great opportunity for kids to share ideas, to listen to each other, to talk with each other, to build language skills, and develop ideas about reasoning. We talk and laugh and think. PERFECTION!

Our conversation moves on to discussing the Standards of Mathematical Practice, specifically SMP #3: *Create viable arguments and critique the reasoning of others*. On Monday, we had the usual teacher talk about how WODB supports Standard of Mathematical Practice #3. On Tuesday, we had a different conversation because Christopher Danielson posted this statement on Twitter:

Tuesday’s conversation was different. More serious. More focused on *our responsibility* to help our students develop good habits to use while they work on interesting and perplexing questions, scenarios, tasks, and problems.

Thank you, Christopher, on behalf of our kiddos.