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My Favorite No - A Math Intervention Strategy for K-12 Classrooms

found in: mathematics, critical thinking, problem solving

My Favorite No is a great assessment activity that turns students’ mistakes into collective opportunities for learning. It can be done with any math topic or content. It takes very little time, so teachers can do it often and weave it into the daily routine of their class.

The premise behind it is simple – students making mistakes is one of the most important tools we have when it comes to helping them learn. We want to expose their mistakes in class, because that is when they can learn something. My Favorite No is a great way to look at student mistakes without shame – it is a empowering thing to tell your class, “This is a really great mistake.”

How does it work?

1. Ask students to solve a math problem on an index card, then turn it in to you.

2. Sort the cards into piles for correct and incorrect answers. Take a moment to find an especially good mistake – one that lots of students make or one that highlights an important math concept. Recopy the incorrect answer to a new card, so that student handwriting can’t be recognized.

3. Ask students to identify what was done well. Then ask them to find where the mistake occurred. Have them explain and justify their thinking.

This idea can be used as bell work or as an exit ticket and provides the teacher with valuable information about how well students understand the concepts you’re teaching.

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