Classroom Close Up: 3rd Grade Math: Carlos & Sara Present Their Solutions with Jennifer Saul

[01:00:30;10]
Narrator: Carlos and Sara are students in Jennifer Saul's third grade class. In this Classroom Close Up segment, we follow them during one math lesson.

Jennifer: "So, before we start our Mental Math, I'd like a review of why we do Mental Math. Why even bother? Sara?"

Sara: "We do Mental Math because there's math all over the world."

Jennifer: "Ah...Carlos?"

Carlos: "Like, when, when, like you're somewhere without pencil or paper, you have nothing to draw on, to check Mental Math, you can just do it in your brain. So, like, math is everywhere."

Jennifer: "Math is everwhere. You're right."

Carlos: We did Mental Math and in Mental Math we did splitting, jumps of ten, and decomposing.

Sara: My favorite is decomposing.

Jennifer: "Sara"

Sara: "I used decomposing. I broke 65 into 60 and 5. I broke 25 into 20 and 5. I added the 60 and the 20 and I got 80. I added the 5 to the 5, and I got 10. I connected the 10 to the 80 and I got 90."

Jennifer: "Show if you agree. Me too. Somebody solve it with another strategy, another Mental Math strategy. Carlos?"

Carlos: "I used splitting. I split 65 to 50 and 15. I added the 50 to the 25, equal. The 50 to the 25. That equal 75. I added the 75 to the 15. That equal 90."

Narrator: Later in the lesson, students are given a word problem and asked to solve it in three different ways, and share their solutions with the class.

Jennifer: "OK. Could I please have Carlos come up? Thank you so much. So, Carlos, explain to us what you did. Presentation voice."

Carlos: "I added all the two's first. 2-4-6-8. I put the eight down. I added. Then I added the ones. 1-2-3-4. Then I put four. Then I added the fours. 4-8-12-16. I put the six down. I carried the one. Then I put the one down, and it was 16 and... $16.48."

Jennifer: "Do you understand his thinking? Great, Carlos. Let's give him a round of applause. Ready?"

Carlos: You don't supposed to be afraid of going up there, like, they're all your friends, still. Like, if, if you say something wroing, they, they don't do nothing. They just, like, correct it by thereself, but they don't say like "You're wrong." Then, but, you, like, you don't have to be, like, like nervous or nothing.

Sara: When you go up there, you know that

Jennifer: "Sara"

Sara: it's like we're a whole family. We're all friends.

Jennifer: "Can yo show how you did this? What did yo make first of all?"

Sara: "First I made a table. In the first two boxes, I put teachers and amount. For the first teacher, it's gonna cost $4.12, then for the second teacher, I added 4 plus 4, $4.12 plus $4.12. Then, I got $8.24. So, I put it there for the second teacher. For the third teacher, I added $.840, 24 cents plus 8, $4.12. Twelve dollars and thirty-six cents. For the fourth teacher, I added $12.36 plus $4.12 and then I got 6, $16.48."

Jennifer: "We need to give Sara a roller coaster cheer. Ready?"

Sara: The cheer feels good 'cause you know that you did a great job.