K-5 friendly lesson
Try one idea, then jump into the activity.These lessons are designed to feel short, friendly, and easy to follow.

Add THREE 2-Digit Numbers

šŸ”ļø Welcome to the towering math stack! When you have three giant numbers on top of each other, you have to be extra careful adding down the column.

Lesson 4

Concept

Stacking three numbers follows the exact same rules! There are just more things to add in the column. šŸŽÆ **The Tower Strategy:** **Example:** 2 4 3 5 + 1 6 --------- 1. **The Ones Column:** (4 + 5 + 6). *Use your ninja tricks! I see a 4 and a 6. That "makes 10". 10 + 5 is 15!* 2. **Regroup!** The answer 15 is too big! * Write the **5** at the bottom. * Carry the **1 ten** all the way to the top of the tens column! 3. **The Tens Column:** (1 + 2 + 3 + 1). * 1+2=3. 3+3=6. 6+1=7. * Write the **7**. 4. **Answer:** **75**! It isn't harder, it's just a slightly longer path to the answer.

Try it

Climb the math tower! **Instructions:** Add down the massive Ones column first. Carry the extra ten! Then add down the massive Tens column. **Problem 1:** (+1) 3 2 1 9 + 2 1 --------- * Ones column: 2 + 9 + 1 = 12. (Write 2, carry 1). * Tens column: 1 + 3 + 1 + 2 = ___ * Total Answer: ___ **Problem 2:** 4 5 2 0 + 1 8 --------- * Answer: ___ **Problem 3:** 1 7 5 2 + 2 3 --------- * (Hint: Make a 10 in the Ones column! 7+3!) * Answer: ___ **Problem 4:** 2 2 3 3 + 4 4 --------- * Answer: ___