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 3-Digit Numbers with Models (No Regrouping)

🧱 Welcome to the Big City! It's time to draw Flats, Rods, and Cubes to stack three giant columns of blocks together.

Lesson 3

Concept

We stacked tens and ones blocks before. Now we just add the giant square Flats to the far left! šŸŽÆ **The "Triple Stack" Method:** **Example: 234 + 152 = ?** 1. **Draw the starting number (234):** * Hundreds: Draw 2 giant squares. * Tens: Draw 3 long rods. * Ones: Draw 4 tiny dots. 2. **Draw the second number underneath (152):** * Hundreds: 1 giant square. * Tens: 5 long rods. * Ones: 2 tiny dots. 3. **Count the columns! (RIGHT TO LEFT!)** * Count Ones dots: 4 + 2 = 6 ones. * Count Tens rods: 3 + 5 = 8 tens. * Count Hundreds squares: 2 + 1 = 3 hundreds. 4. **Answer:** **386**. The blocks make it impossible to get lost.

Try it

Build the giant skyline! **Instructions:** Imagine the Giant squares (100), Long rods (10), and Tiny cubes (1). Count them column by column to find the answer. **Problem 1: 415 + 243 = ?** * Squares: 4 + 2 = ___ * Rods: 1 + 4 = ___ * Cubes: 5 + 3 = ___ * Answer: ___ **Problem 2: 152 + 524 = ?** * Squares: ___ * Rods: ___ * Cubes: ___ * Answer: ___ **Problem 3:** You see a picture: Top row has 3 squares, 0 rods, 6 cubes. Bottom row has 1 square, 4 rods, 2 cubes. * Answer: ___ **Problem 4:** 500 + 192 = ? * (Hint: The top number only has squares!) * Answer: ___