K-5 friendly lesson

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

Mixed Practice: 3-Digit Addition

⚡️ Lightning Round! Can you spot the tricks? Use compensation for the 9s, and Hundreds-dials for the zeros. Stack the rest!

Lesson 6

Concept

You possess three different strategies for three-digit math. 🎯 **The Strategy Selector:** 1. **The Dial Strategy:** Does the number end in two zeros? (Like 400). Don't stack it! Just spin the hundreds dial in your brain! (235 + 400 = 635). 2. **The Compensation Strategy:** Does the number end in 98 or 99? Pretend it's a hundred! (+100, -1). 3. **The Stacking Strategy:** Is it a really messy number like 347? Grab your pencil and stack it up right away! Do NOT try mental math.

Try it

Pick your weapon! **Instructions:** Look at the numbers before you start. Use the smartest trick possible! **Problem 1: 412 + 300 = ?** * (Hey! It's two zeros! Just spin the hundreds dial!) * Answer: ___ **Problem 2: 250 + 199 = ?** * (Hey! It's a 99! Pretend it's 200, subtract 1!) * Answer: ___ **Problem 3: 134 + 252 = ?** * (Messy numbers! Stack them up!) 1 3 4 + 2 5 2 -------- * Answer: ___ **Problem 4: 512 + 398 = ?** * Answer: ___