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* *Reflection:
Subtraction in Context II - Section 3: Concept development

As seen in my reflection video, students did very well today using the phrase that pays. I am happy that I made the instructional decision to have students work independently and then talk with their learning partners. Students who may have relied on their partner to do "the work" had to think through problems and persevere on their own before talking with their partner.

I know the more I encourage and give students opportunities to discuss their math thinking, the better they will be at discussing their thinking. I have some students who do very typical fourth grade things for this time of year. For example, I have a pair that almost refuses to talk to each other and will hardly look at each other when they do talk. I just keep encouraging them and give them starting questions if the phrase that pays isn't enough to get them going. I might ask them if their answers are the same and if they can prove they used the same strategy? This gives students an entry point to discuss which can't be answered with a yes or no response. Anther one of my students gets very embarrassed and red faced when having to explain her thinking. These sorts of things don't bother me, because from past experience, these are all very typical fourth grade reactions. I am confident that by the end of the year, my math class talk will look and feel very different. I expect that the phrase that pays will become less of the focus and the "talk" will become more genuine and heartfelt by the students. At this point, it is still something they view as an assignment they have to do. I truly believe this will change as the develop into mathematical critical thinkers.

*New Phrase Paid*

*New Phrase Paid*

# Subtraction in Context II

Lesson 3 of 5

## Objective: Students will be able to use the standard subtraction algorithm, and apply the algorithm to solve word problems while utilizing Math Practice Standard 3.

#### Warm Up

*5 min*

Students will begin this lesson with rounding numbers to the nearest thousand, ten thousand, and hundred thousand using a strategy I call Pass and Read. Each student has an index card. I have them think of a four digit number, a five digit number, and a six digit number. They record these numbers on their index card. They then round each of those numbers to the largest place. Students should do this quickly. I only give them 3 minutes. If they don't have an answer at the end of three minutes, this is sign to me that they need more practice with rounding or building number sense. The directions for pass and read directions are located here.

I chose to do a rounding review for today's warm up since students have a place value assessment coming up. I am able to observe students who need more support with this concept and reach them before the assessment.

#### Resources

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#### Concept development

*45 min*

I start this lesson by introducing the "new phrase that pays," *To solve this problem I ______. *Today's lesson will focus on Math Practice Standard 3 by having students communicate their math thinking. As stated on www.insidemathematics.org, teachers who are developing students’ capacity to "construct viable arguments and critique the reasoning of others" **require **their students to engage in active mathematical discourse. This might involve having students explain and discuss their thinking processes aloud, or signaling agreement/disagreement with a hand signal. I let students know that I want to catch as many students as I can using this phrase.

Students have had several opportunities to solve word problems with their learning partner, today they will work independently for 5 minutes and then turn and talk for 2 minutes. The 5 minutes of independent working time is usually enough time for students to solve one word problem, draw a tape diagram, and check their work. Students will solve the word problem, follow all directions, and when I give a signal, they talk to their learning partner. I use the website www.timeme.com so students can also visually observe the time left.

During the two minute talking time, I listen for students who are using the phrase that pays as well as listen for students who may disagree on answers. (The linked short video clip shows two students revising their work during the 2 minute talk time. You can hear the boy saying, "So, I think you're right.") This is a very quick two minutes and my classroom buzzes during this activity. I chose specifically one step subtraction problems with large numbers for this activity because I wanted to concentrate on the phrase that pays. If I had done two step word problems, students would need more time and energy to focus in on the content of those problem. By using the one step word problem, my students are still able to work towards mastery of 4.NBT.4 as well as master strategies and models to be used in order to master 4.OA.3 which states students will solve multistep word problems. When my students are confident in their math thinking, and using models to make sense of mathematical situations, I believe they will be more ready to tackle 4.OA.3, but I will begin with smaller numbers in my next unit.

When the two minutes are up, students resume working independently. Students may chose to revise any work if their partner has convinced them of a different answer or strategy.

Students are able to complete the word problems in the time allotted. They work on the front side as homework.

Students using phrase that pays shows students talking during the 2 minute talk time.

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To wrap up this lesson, I ask students why it is important to communicate their math thinking. I then ask them what mathematical practice they used today and direct their attention to the posters in my classroom. Many students respond with phrases like: "We can learn from each other," "_______ might have another way of doing the same type of problem that makes more sense to me," and "When we talk about our thinking it helps our brains grow."

*This last phrase is specific to my students. I talk a lot about the brain and how it grows and myelinizes. Myelin is white matter in the brain that forms layers that make nerve impulses faster and stronger and which a number of researchers suggest increases learning. The amount of myelin and its density seems to increase through practice and makes what you are learning to do more automatic. The idea of deliberate practice comes in because we have to ensure that myelin forms to increase and strengthen the right impulse. For more information about student learning and myelin, you can check out this blog post. The author, Larry Ferlazzo, discusses current events, trends, and educational issues and interests. This is a blog I follow and check weekly. *

#### Resources

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###### Real World Word Problems with Multiplication and Division (Day 2)

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- UNIT 1: Getting to Know You- First Days of School
- UNIT 2: Multiplication with Whole Numbers
- UNIT 3: Place Value
- UNIT 4: Understanding Division and Remainders
- UNIT 5: Operations with Fractions
- UNIT 6: Fraction Equivalents and Ordering Fractions
- UNIT 7: Division with Whole Numbers
- UNIT 8: Place value
- UNIT 9: Geometry
- UNIT 10: Measurment
- UNIT 11: Fractions and Decimals