Learning Intention: Students will be able to accurately add two digit numbers within 20.

Materials Needed: •Sets of 20 two-digit numbers •Whiteboard for teacher demonstration

Lesson Plan: 1. Begin by introducing the concept of adding two-digit numbers within 20. Explain that in this lesson, we will practice adding two-digit numbers without regrouping.

1. Ask the class to generate a few examples of two-digit numbers within 20. Write them on the whiteboard.

2. Demonstrate how to add two two-digit numbers without regrouping by using the numbers on the board. Fill in the addition chart and walk the class through each step as you go.

3. Ask the class to generate 3 more examples and have them solve it themselves using the same chart. Provide support as needed.

4. Introduce the concept of exchanging, which will allow us to add two-digit numbers larger than 20. Demonstrate this with the example numbers on the board and fill in a new chart for the steps.

5. Hand out sets of two-digit numbers within 20 cards to each student. Have them work with a partner to practice adding them.

6. Ask students to generate 3 two-digit numbers within 20 and solve them themselves.

7. Provide feedback to students as they practice.

8. As a final review, have the class complete an assessment with more two-digit number addition problems, both with and without exchanging.

Closure: Recap the concept of adding two-digit numbers within 20. Ask students to list key points they have learned. Remind them that they are now able to accurately add two-digit numbers without regrouping and with exchanging.