Subtracting from 4
Lesson 8 of 19
Objective: Students will be to able solve subtraction equations.
Problem of the Day
I start each math lesson with a Problem of the Day. I use the procedures outlined here on Problem of the Day Procedures.
Today's Problem of the Day:
There were 10 basketballs in the gym. The teacher put 4 of them away. How many
basketballs are left in the gym?
I set this problem up with some structure to help the students organize their thinking. I give a blank number sentence to encourage students to write an equation. I also include a basketball set to infinite cloner. If you do not have a SMART Board, you can use the PDF and manipulatives, pictures or students drawings.
Since we do this whole group, I have one student come up and do this problem. I remind the student to check their work when they are finished and have the class tell if they agree or disagree by showing a thumbs up or thumbs down.
Presentation of Lesson
I start this lesson by reading Five Little Monkeys Jumping on the Bed by Eileen Christelow. Check it out here. I model this with monkey manipulatives much like I did back in the lesson on introducing 5. While this book is about 5 monkeys I start talking about 4 after the first monkey falls off the bed. I write the number 4 on the board.
What number is this? Today we are going to look at what happens when we take away from 4. Let's start by using what we already have on our bodies that can help us count. Put up 4 fingers. If I have 4 and I take away 0, how many fingers do I still have up?
I show it on my fingers and write the equation on the board. 4 - 0 = 4 We continue to read and as each monkey falls off, I have students model with their fingers and I write the other possibilities 4-1, 4-2, 4-3 and 4-4 on the board.
When we are finished, I tell students that they are going to be practicing taking away from 4 on a Take Away From 4 Worksheet.
We are going to work on this paper together. When you get to your seat, do not touch your cup of counters. You need to get out a pencil and put your name on your paper. When your name is on your paper hold your pencil in the air, that will let me know that you are ready to start.
I use the procedures outlined here on the Paper Procedures. Prior to this lesson, I placed a plastic cup at each students' place containing four color tiles.
Use your color tiles to model each equation. Write the numbers to complete the equations.
The first thing the directions tell you to do is use the color tiles to model each equation. You will notice that the last question does not have an equation to model. For this question, you will need to use the color tiles to come up with your own way to subtract from 4.
We work through the first 5 questions together. For the last question, I show one way to do it on the SMARTBoard. I then allow the students to come up with their own way. I walk around and make sure that students are correctly counting writing their equations. When students are finished with their paper, they can put it in the basket and get their center.
The centers for this week are:
- Addition Word Problems (I used a Lakeshore Read and Solve Word Problems Center. You can also use these Addition Word Problem Cards that I made.)
- Easter Egg Addition (Available free from Teachers Pay Teachers)
- Goldfish Graphing (Available free from Teachers Pay Teachers)
- Piggy Bank Addition Mat (Available free from Mrs. Ricca's Kindergarten)
- Sweater Math Match-Up (Available free from Teachers Pay Teachers)
I quickly circulate to make sure students are engaged and do not have any questions about how to complete the centers. Because of the trouble during our addition unit, I decided not to introduce any subtraction centers this early in the subtraction unit.
I pull 3 groups (5-10 minutes depending on need). We are working on writing equations in all groups. I verbally give the group an equation. I have them write it and then solve it using manipulatives. With students who are able to do this easily, I also have them try with drawing pictures instead of manipulatives.
Prior to clean up, I check in with the other tables to see how the centers are going. My students have been struggling with getting cleaned up quickly and quietly after centers. Lately I have been using counting down from 20 slowly instead of a clean up song. Counting backwards is as critical as counting up. Students need to be able to know the number that comes before, as well as after, any given number (w/i 10, w/i 20, etc.). Counting back is a critical strategy for subtraction.
The students like to count backwards with me as they clean up and I can lengthen or reduce the clean up time based on how students are doing and how much time we have.
To close, I put a student's paper on the document camera a project it on the SMART Board and have that student explain their work. I have the class read the equation using the words minus and equals. I mention positive things noticed during centers as well as something that needs to be better next time.
I review what we did during our whole group lesson. "Today we learned about taking away from 4. Tomorrow we are going to continue this series of lessons where where we practice subtracting from a given number!"