Yesterday we learned what “one less” means. We saw that one less means to take away 1, it means our number is getting smaller.
Today we are going to practice using one less and one more language. We are also going to look at what this looks like on the number line.
By the end of 1st grade, I want you to have a number line in your brain. You won’t need a hundreds chart! You will be able to use your brain number line everywhere you go. 1 more and 1 less helps you make your brain number line stronger.
Objective : Your thinking job today is: How can I use the number line to show 1 more and 1 less?
Present and Practice Definitions:
Remember yesterday we said, “one less” means take away 1. Today we are going to also include 1 more, we all know what 1 more means. 1 more is when we want to add 1 more of something.
(Show hand motions for both-see video for the hand motions we use!)
Present Problem: The CCSS emphasizes a problem based approach to mathematics. Students engage in this real life scenario to help them visualize the meaning of 1 less.
Now I have 27 pencils.
Ms. Anderson has 1 less than me.
How many pencils does she have?
Students solve this problem by themselves/with a partner at their desks.
Guiding questions before they go: These questions help students learn the types of questions they will eventually need to ask themselves before they go and try to solve a problem on their own. This helps them with MP1, Make sense of problems and persevere in solving them.
I'll quickly share out a cubes and a number line strategy. I'll use these strategies as a jumping off point for using the number line in the game for today.
Game Rules and Practice:
I'll teach rules and practice the game with students. I'll use guiding questions for students to pay attention to the math embedded in the game.
1. Partner 1, Highlight a number on the number line. Ask: What’s one less? How do you know?
2. Partner 2, Hop to 1 less like a frog!
3. Partner 1: Asks, “What’s one more? How do you know?”
4. Partner 2: Hop to 1 more like a frog!
Students use number lines (see link for free number lines) to play with a partner.
Students who need more practice can use the number line for 0-20. Students who are ready can use number lines for 21-40.
See attached document for recording sheet.
Our thinking job was to figure out how we could find a number that is 1 more and 1 less using the number line as a tool. We practice 1 more and 1 less to help us develop a number line that is stuck in our brain.
I'll play 1-2 more rounds as a class to close out the day.