### Objectives & Outcomes

• Students will be able to add and subtract two-digit numbers using their knowledge of place value, basic addition and subtraction facts, and strategies for solving problems.

### Materials

• Whiteboard or chalkboard and markers
• Copies of worksheets with addition and subtraction problems (one-digit numbers are ideal for beginners)
• Colored pencils or markers

### Warm-up

• Review the concept of place value by using a number chart to show how the number 1000 is made up of hundreds, tens, and ones. Ask students to identify the hundreds, tens, and ones in the number 1000.

### Direct Instruction

• Introduce the concept of addition by using small, matching cards with numbers on them. Ask students to arrange the cards in order from smallest to largest to demonstrate understanding of the concept of addition.
• Explain that when we add two or more numbers, we are joining the numbers to form a bigger number.
• Demonstrate how to solve an addition problem by using a number chart, and have students watch and follow along. Start with the smallest number and add each number after it to form the final, larger number.
• Introduce the concept of subtraction by using small, matching cards with numbers on them. Ask students to arrange the cards in order from largest to smallest to demonstrate understanding of the concept of subtraction.
• Explain that when we subtract one number from another, we are taking away one number to form a smaller number.
• Demonstrate how to solve a subtraction problem by using a number chart, and have students watch and follow along. Start with the largest number and subtract each number after it to form the final, smaller number.

### Guided Practice

• Have students work in pairs and solve addition and subtraction problems using number charts. Provide support and guidance as needed.

### Independent Practice

• Have students work in small groups to create a classroom-wide addition and subtraction game. Encourage them to be creative and include a variety of types of problems.

### Closure

• Review the key concepts of addition and subtraction and the strategies and skills that the students have learned.

### Assessment

• Observe the students during the guided practice and independent practice to assess their understanding of the addition and subtraction principles and their ability to apply the strategies and skills.
• Collect and review the students' work during the independent practice to assess their ability to solve addition and subtraction problems.