Learning Intention: At the end of the lesson, students will be able to add 2-digit numbers up to 20.

Objectives: 1. Students will be able to identify and explain what addition is. 2. Students will be able to accurately add two 2-digit numbers up to 20. 3. Students will be able to apply strategies to solve addition problems.

Materials: - Pencils and paper - Variety of 2-digit numbers (For example: flashcards, number cubes, number cards, etc) - Addition strategies posters

Introduction: Ask students how they would define addition. Explain to the class that addition is combining two numbers to make one big number, and that today they are going to be learning how to add two two-digit numbers up to 20.

Step 1: Review basic addition facts with students using flashcards, number cubes, or number cards. Ask them to give the answer to addition questions with two numbers up to 20.

Step 2: Introduce students to the addition strategies that can be used to solve addition problems. Post the addition strategies posters. Explain to students that these strategies can be used to help them solve problems easily.

Step 3: Have students practice solving addition problems with 2-digit numbers up to 20. Encourage them to use the strategies they have learned to solve the problems.

Closure: Lead a class discussion asking students to summarize the lesson. Ask them to explain what addition is and what strategies can be used to solve addition problems.