## Join Change Unknown problem - Section 2: Independent/partner work

# Counting On

Lesson 2 of 5

## Objective: SWBAT count on from the bigger number.

#### Number Work

*15 min*

Sometimes connections to the real world surface so naturally, it's hard not to take advantage. The day I am teaching this lesson happens to be 11-12-13, which makes for exciting number work in first grade (though you can use these or similar numbers even if you're not teaching this lesson on this particular date). I'm sure when we write the date during calendar someone will point out, "Look it is 11, 12, 13." I won't point this out at first, I want the students to make those discoveries no matter how small or large. Again, you can use this for lots of dates, not just 11-12-13, or you can find other ways to tie in interesting real world connections.

Using their math notebooks students are to record ways to make 11, 12, 13.

I will write an 11, 12, 13 at the top of the board. They are to do the same on their papers. They can draw lines to distinguish the groups or just leave spaces. They are to come up with equations with 2 addends, that have the sum as the top number.

I am saying 2 addends because I am hoping to lead them to the idea that 10+1=11, 10+2=12, 10+3=13. How just going up by one, one addend can stay the same.

I will give them 5-10 minutes to record their thinking and then we will meet back at the carpet to share out some of their equations.

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#### Independent/partner work

*20 min*

Today the students are going to solve a problem in their notebooks. I like to write problems that use the students as "characters." This helps students stay motivated and engaged. I choose to write a missing addend problem to work on the counting on strategy. I have put in larger numbers to make it more difficult for those students who want to count all. This will hopefully help the students to move to a counting on strategy. The worksheet that is included as multiple copies of the same problem. I cut the problems apart and tape them into the students notebooks. That works well for my teaching style.

I'll start off by saying, "*We have a new problem to unpack. and Mia and Braeden are the main characters today,"*

I will read the problem aloud, "*Mia had 6 rocks in her rock collection. Braeden gave her some more. Now Mia has 9 rocks. How many rocks did Braeden give her?*"

I'll ask the students: *What do we know? What do we need to find out? **How is this problem different from Zoey's bracelet problem yesterday? *

I want a student to point out that yesterday we had to find the total number of bracelets that Zoey had at the end of the story. Today we need to figure out the middle part, or missing addend. We know that Mia has 9 rocks at the end of the story.

It is very important to have the students think about what the problem is asking them, and then discuss what that means mathematically. The more students discuss the better they understand their mathematical thinking. As they discuss they are being encouraged to communicate precisely (MP6).

Students will once again work with a partner.

I have partnered them up high/high, medium/medium, or medium/emerging. I do this because want students to be successful when working with a partner, sometimes if a high student is with a medium or emerging student the discussion isn't beneficial for all involved. I want each student to be able to be an active member of the duo. I want all students to be challenged, so I have different entry points, depending on where students are in their learning. Also, my high/high students have different number choices to challenge them.

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#### Wrap up

*10 min*

I feel is is very important to conference with a student before they share out. I have had students not exactly remember what they did, get flustered while sharing, and move to different number choices then we were discussing. If we've met then their strategy is fresh in their mind and I can guide them through *their own* the process. I'm not going to add anything they didn't do, but sometimes I can help them formulate that into "math talk" or mathematician talk.

After I have conferenced with partners, I will ask certain students to share out their strategies. I am looking for a hierarchy of levels. I will start with a simple direct modeler and move into more sophisticated strategies, as in decomposing numbers. I try and get at least 4 or 5 students to share out. I like to have conferenced with the student before they share out their strategy. That way I know what they were thinking as they were solving.

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