SWBAT solve 2 part story problems with different equations.

This Grinch inspired lesson pushes 1st graders to attempt 2 part story problems. It also is a great way to introduce the topic in 2nd grade!

5 minutes

Before teaching this lesson, I read How the Grinch Stole Christmas with my students. If you haven't read it yet, you'll need a little longer before you start the math lesson to read this story aloud. **See attached video:Why use the Grinch? Connecting to Lit Standards for why I connected this lesson to the Grinch!**

**Review**

We read about the Grinch and we saw he changed. At first he stole Christmas presents from the Who's. But after he learns the real meaning of Christmas, he brings some back. We have story problems today that show us how the Grinch changed.

**Connect**

Story problems do not always have one action. Sometimes one action happens and then something else happens right after, just like in the Grinch!

**Objective:**

Your thinking job is: How can I solve story problems where 2 actions happen?

*This objective pushes MP1, Make sense of problems and persevere in solving them. Students learn how to handle a problem where 2 actions take place!*

15 minutes

The first problem I'll present to students has low numbers so students can experiment with solving 2 part story problems without dealing with complex numbers.

Present problem:

There were 10 presents in the Who houses. The Grinch stole 5 of them. How many presents are still in the Who houses?

- Solve the problem on the rug. Then share with a partner how you solved it.
- I'll quickly share out how a few students solved, then have students help me write a matching number sentence.
- In that story problem, had Grinch learned the real meaning of Christmas yet? No! He hasn't changed yet.

Now the Grinch brings 6 presents to the Who houses. How many presents do the Whos have now?

Guiding Questions:

- Focus on character change: What happened to the Grinch?
- What number tells us how many presents were in the Who houses? Is it in the problem? No! It is the answer to the first problem.
- What symbol represents the second problem? + or -?

20 minutes

I'll have students solve the second part of the problem at their desks. After 7 minutes of work time, I'll have students bring their work to the rug and share it with a partner.

I'll choose just one strategy to share because I want to focus more on how students worked through the problem, less on how they actually solved it.

Guiding Questions:

- How did they write the number sentence? Why did they write it that way?
- What does the first number in the number sentence tell us?
- Why did we use a + here but a - in the first problem?

Partner talk: How was your strategy the same or different from your teammate?

15 minutes

Students solve a 2 part story problem at their desks. Students also have a writing portion on the second page. There is a word bank there for students to help them with explaining their thinking. This is aligned with the CCSS emphasis on writing across the curriculum.

The numbers in the story problems are differentiated for students.

**Group A: Intervention**

Students use numbers under 15, cubes provided

**Group B: Right on Track**

Students use numbers under 30

**Group C: Extension**

Students use numbers under 100

**See attached pdf for the independent worksheet. The numbers are left out of the story problems so teachers can write in numbers that are most appropriate for their students. **

10 minutes

Students share their work with a partner before closing out for the day. To celebrate our learning, we will sing and listen to The Grinch Song on youtube!