Unit 3: Reasoning and Explaining (MP2 and MP3)

# 3.4.2 Students Revise and Share Work with Partner

### Step 2. Students individually meet with the teacher, then revise work

The teacher met with each student, read their responses, and asked questions to prompt more complete responses. The questions asked were:

“How do you know that 5 is an odd number?”

“How did you know that it was 5 and not 7?”

“Can you show me another way?”

“Why doesn’t 4 + 3 + 2 work? It totals 9.”

“What does 5 refer to? The 3? The 1?”

“Could you use what you learned in the first problem to help with the second problem?”

### Step 3. Students share with a partner and revise

Often, when a student is explaining a solution to someone else they discover gaps, mistakes, or incomplete responses. In the following dialogue, Leslie has taught her strategy to Stephanie and they share their method with the teacher. Look for points where the girls correct themselves or refine their argument as they are talking.

 Teacher: Tell me what you have going on here. Stephanie: I grabbed 9 pencils for the roses, 9 erasers for the tulips, and 9 pens for the lilies. Then I lined up all the odd numbers. Leslie: So, I put: 1, 3 ... Stephanie: 5, 7 and 9. Leslie: So, we're going to pretend like that this box is like the vase for the … and she's going to try to put in each flower into the rose, I mean into the vase, so that we have like odd numbers. So, try. Stephanie: So, first I'm going to start with the roses. Leslie: There are more tulips than roses. Stephanie: Nine pencils for the roses. These are the tulips [pointing to the 9 erasers]. Leslie: So we're going to put 5 tulips. 1, 2, 3, 4, 5. And since the tulips have to be bigger than the roses, we're going to put... Stephanie: 3 roses. Leslie: Then we're going to put 1... Stephanie: Tulip. Leslie: 1 lily. Because there are more roses than lilies. Then we're going to count it up, so it's going to be 1, 2, 3, 4, 5, 6, 7, 8, 9. Stephanie: 9