Mastering Two-Digit Subtraction with Regrouping
2nd Grade Mathematics Building Fluency with Place Value 35 Minutes of Mathematical Discovery
Number Talk Warm-Up
Look at this problem: 42 - 27 What strategies could we use? Think about tens and ones! Share your thinking with a partner
Understanding Regrouping
Sometimes we need to 'borrow' from the tens place When ones digit is too small to subtract from We trade 1 ten for 10 ones This makes subtraction possible!
Step-by-Step: 53 - 26
Partner Practice: Subtraction Stories
Work with your math partner Read the story problem together Use base-ten blocks to solve Explain your strategy to each other Check your work together
Independent Practice Time
Solve 10 subtraction problems Some need regrouping, some don't Use your dry erase board first Show your work clearly Raise your hand if you need help
Exit Ticket Challenge
Solve: 64 - 38 Show your work Write one thing you learned today Turn in your work before leaving
Great Job, Mathematicians!
"You can use place value to solve any subtraction problem!" Remember: When you need more ones, trade a ten! Practice makes you stronger at math You're becoming subtraction experts!