Lesson Plan for Grade 2 - Mathematics - Addition and Subtraction (two-digit numbers)

### Lesson Plan: Addition and Subtraction (Two-Digit Numbers) **Grade:** 2 **Subject:** Mathematics **Topic:** Addition and Subtraction (Two-Digit Numbers) **Duration:** 1 hour --- #### Objectives: 1. Students will understand the process of adding and subtracting two-digit numbers with and without regrouping. 2. Students will enhance their problem-solving skills using addition and subtraction of two-digit numbers. 3. Students will practice and apply their skills through various activities and exercises. #### Materials Needed: - Whiteboard and markers - Student math notebooks - Pencils and erasers - Base ten blocks or math manipulatives - Worksheets with addition and subtraction problems - Flashcards with two-digit addition and subtraction problems - Chart paper and markers #### Common Core Standards: - CCSS.MATH.CONTENT.2.NBT.B.5: Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction. --- #### Lesson Structure: **1. Warm-Up Activity (10 minutes)** - Begin with a quick mental math activity. Ask students to solve simple one-digit addition and subtraction problems aloud. - Examples: - 7 + 5 = ? - 9 - 3 = ? - 8 + 4 = ? - 14 - 6 = ? **2. Introduction to Two-Digit Addition (10 minutes)** - Explain that today we will be learning how to add two-digit numbers. - Demonstrate on the whiteboard: - Example: 34 + 28 - Write both numbers vertically. - Add the ones: 4 + 8 = 12. Write down 2 and carry over 1 to the tens place. - Add the tens: 3 + 2 = 5 + 1 (carried over) = 6. - Answer: 34 + 28 = 62. - Use base ten blocks to visually represent the problem and solution. **3. Guided Practice: Two-Digit Addition (10 minutes)** - Solve a few problems together as a class: - Problems: 47 + 35, 58 + 23, 29 + 14 - Ask students to come up to the board and solve a problem using the steps demonstrated. **4. Introduction to Two-Digit Subtraction (10 minutes)** - Explain subtraction with two-digit numbers, including borrowing. - Demonstrate on the whiteboard: - Example: 52 - 19 - Write both numbers vertically. - Subtract the ones: 2 - 9 (since you can't subtract 9 from 2, borrow 1 from the tens place). - Change 2 to 12, and 5 becomes 4. - Subtract the ones: 12 - 9 = 3. - Subtract the tens: 4 - 1 = 3. - Answer: 52 - 19 = 33. - Use base ten blocks to visually represent the problem and solution. **5. Guided Practice: Two-Digit Subtraction (10 minutes)** - Solve a few problems together as a class: - Problems: 63 - 27, 81 - 34, 45 - 18 - Ask students to come up to the board and solve a problem using the steps demonstrated. **6. Independent Practice (10 minutes)** - Hand out worksheets with a mix of addition and subtraction problems for students to solve independently. - Problems will include both with and without regrouping. **7. Review and Discuss (5 minutes)** - Review the worksheet together as a class, discussing any common mistakes and ensuring understanding. - Example problems to go over: - 54 + 39, 72 - 28 **8. Closing Activity (5 minutes)** - Play a quick flashcard game where students solve two-digit addition and subtraction problems individually. - Encourage students to explain their process for solving each problem. --- #### Assessment: - Observe students' participation during guided practice. - Review students' worksheets to assess their understanding. - Note which strategies students use during independent and group activities. #### Homework: - Assign a worksheet with additional two-digit addition and subtraction problems for homework to reinforce the day's lesson. --- #### Reflection: Post-lesson, reflect on the success of the activities and the students' understanding. Adjust future lesson plans based on the students' performance and areas where they might need additional support or practice.