I'm Jealous! Comparison Story Problems
Lesson 2 of 7
Objective: SWBAT solve comparison word problems.
Objective & Hook
This standard (1.OA.1) asks students to solve all kinds of word problems, including problems where they must compare two known quantities. In this lesson, students make sense of comparison problems (MP1) and think critically about what those problems are asking. Then students focus on efficiency-students may start with direct modeling with cubes, but this lesson asks them to also look at how other students solve problems.
Yesterday, we played a game where we were looking at how many more one partner had than another. Today, we are going to look at how we can compare 2 numbers in a story problem. You are going to get 5 minutes to play the game from yesterday to practice comparing the numbers.
Connect to the Real World:
This is important because we often have to think about comparisons-who has more points? Who has fewer treats?
Your thinking job is: What strategies can I use to solve “How many more” problems quickly? How can I show what I did?
I have a story problem to tell you about. This story is all about a problem that Coach Brown has. He sent it to us to figure out!
Present Problem: Coach Brown has 5 basketballs. Coach Williams has 11 basketballs. Coach Brown is jealous! Who has more basketballs? How many more?
- What is this problem asking us to figure out? (have students retell in partners) Is this problem asking me how many basketballs they have in all? How do you know?
- Coach Brown wants to know how many more basketballs Coach Williams has. Why would Coach want to know that? (Because Coach doesn’t want to have less, Coach doesn’t like it that Coach W has more, Coach wants to figure out how many he needs to buy to catch up to Coach Williams)
- When we ask how many more questions, we are getting at all these questions-we are figuring out how many Coach needs to catch up to Coach Williams.
- I could rewrite the question like this: How many basketballs does Coach need to buy to catch up to Coach Williams?
Take a second to think about how we could solve this problem.
Partner Talk: How might we go about solving this problem? What might be a good first step? Think about our game from yesterday.
Student Work Time and Share
Student Work Time:
Students solve this problem at their desks, then come back together and do a student share. You can watch how one student solved in the attached Direct Modeling strategy video. In this video, I discuss the strategy with this student and his strategy was one I chose to share during the strategy share.
Strategy Share: I'll choose 2 students to share their strategies and our discussion will be around comparing the two strategies. I chose one direct modeling strategy and another student who used counting on.
- How did each person show the “extras”?
- Model number sentence: They both have 11. You broke off the ones that were the same, and they had extra. 11 -5 = 6.
Group A: Intervention Group
Students get story problems with numbers under 10. Students use cubes as a support, and create a graph to match the data. Because students will have had so much experience with data comparison, this will give them an extra scaffold.
Group B: Right on Track
Students solve problems with numbers under 20.
- Adding the Numbers together: Watch the video to see how I handle the misconception of adding the numbers together instead of comparing them.
- See the Using Base 10 video to see how one student used the concept of 10 to solve.
- Watch a student use Known Facts to help them solve-this is the highest strategy students will likely use for this number set.
Group C: Extension
Students solve problems with numbers under 50.
Independent Practice problems are attached: Comparison Story Problems.pdf.
Bring students back together and share a strategy of a student who used counting on or number facts. I want the last strategy students hear to be a strategy that moves students away from direct modeling! This sets students up for future comparison story problems.