In this sample lesson plan, students represent addition and subtraction with objects and actions. The plan is designed for kindergarten students.** **It requires **three class periods of 30 to 45 minutes each**.

## Objective

The objective of this lesson is for students to represent addition and subtraction with objects and actions to understand the concepts of adding to and taking from. The key vocabulary words in this lesson are addition, subtraction, together and apart.

## Common Core Standard Met

This lesson plan satisfies the following Common Core standard in the Operations and Algebraic Thinking category and Understanding Addition as Putting Together and Adding To and Understand Subtraction as Taking Apart and Taking From sub-category.

This lesson meets standard K.OA.1: Represent addition and subtraction with objects, fingers, mental images, drawings, sounds (e.g., claps), acting out situations, verbal explanations, expressions or equations.

## Materials

- Pencils
- Paper
- Sticky notes
- Cereal in small baggies for each child
- Overhead projector

## Key Terms

- Addition
- Subtraction
- Together
- Apart

## Lesson Introduction

The day before the lesson, write 1 + 1 and 3 - 2 on the blackboard. Give each student a sticky note, and see if they know how to solve the problems. If a large number of students successfully answer these problems, you can begin this lesson midway through the procedures described below.

## Instruction

- Write 1 + 1 on the blackboard. Ask students if they know what this means. Put one pencil in one hand, and one pencil in your other hand. Show students that this means one (pencil) and one (pencil) together equal two pencils. Bring your hands together to reinforce the concept.
- Draw two flowers on the board. Write down a plus sign followed by three more flowers. Say aloud, “Two flowers together with three flowers make what?” The students should be able to count and answer five flowers. Then, write down 2 + 3 = 5 to show how to record equations like this.

## Activity

- Give each student a bag of cereal and a piece of paper. Together, do the following problems and say them like this (adjust as you see fit, depending on other vocabulary words you use in the math classroom): Allow the students to eat some of their cereal as soon as they write down the correct equation. Continue with problems such as these until the students feel comfortable with addition.
- Say "4 pieces together with 1 piece is 5." Write 4 + 1 = 5 and ask the students to write it down too.
- Say "6 pieces together with 2 pieces is 8." Write 6 + 2 = 8 or the board and ask the students to write it down.
- Say "3 pieces together with 6 pieces is 9." Write 3 + 6 = 9 and ask the students to write it down.

- The practice with addition should make the subtraction concept a bit easier. Pull out five pieces of cereal from your bag and put them on the overhead projector. Ask students, “How many do I have?” After they answer, eat two of the pieces of cereal. Ask “Now how many do I have?” Discuss that if you start with five pieces and then take away two, you have three pieces left over. Repeat this with the students several times. Have them take out three pieces of cereal from their bags, eat one and tell you how many are left over. Tell them that there is a way to record this on paper.
- Together, do the following problems and say them like this (adjust as you see fit):
- Say "6 pieces, take away 2 pieces, is 4 left over." Write 6 - 2 = 4 and ask the students to write it as well.
- Say "8 pieces, take away 1 piece, is 7 left over." Write 8 - 1 = 7 and ask the students to write it.
- Say "3 pieces, take away 2 pieces, is 1 left over." Write 3 - 2 = 1 and ask the students to write it.

- After the students have practiced this, it’s time to have them create their own simple problems. Divide them into groups of 4 or 5 and tell them that they can make their own addition or subtraction problems for the class. They can use their fingers (5 + 5 = 10), their books, their pencils, their crayons or even each other. Demonstrate 3 + 1 = 4 by bringing up three students and then asking another to come to the front of the class.
- Give students a few minutes to think of a problem. Walk around the room to assist with their thinking.
- Ask the groups to show their problems to the class and have the seated students record the problems on a piece of paper.

## Differentiation

- In step four, separate students into tiered groups and adjust problems based on complexity and number of steps. Support struggling students by spending more time with these groups and challenge advanced students by asking them to experiment with different types of counting, such as with their fingers or even with each other.

## Assessment

Repeat steps six through eight together as a class at the end of math class for a week or so. Then, have groups demonstrate a problem and do not discuss it as a class. Use this as an assessment for their portfolio or to discuss with parents.

## Lesson Extensions

Ask students to go home and describe to their family what putting together and taking away means and what it looks like on paper. Have a family member sign off that this discussion took place.