Add 2-Digit Numbers with Regrouping (438)

Teaching Notes

Emphasize place value and the concept of regrouping ten ones as one ten. Encourage students to start adding from the ones column.

Vocabulary

Regroup: To exchange 10 ones for 1 ten, or 10 tens for 1 hundred.

Carry over: Moving a value to the next higher place value column.

Common Mistakes

• Forgetting to regroup (carry over) the tens.
• Adding the tens column before the ones column.
• Incorrectly adding the regrouped number.

Differentiation

Discussion Questions

• Why is it important to start adding from the ones place?
• What does 'regrouping' mean when adding numbers?
• How is regrouping similar to bundling sticks or counting groups of ten?
• What would happen if you forgot to regroup in an addition problem?

Extension Activities

• Add prices with regrouping.
• Solve word problems.
• Play regrouping games.

Parent Tip

Use base-ten blocks to visually demonstrate regrouping ones into tens.

Skill Cluster

Number Operations and Place Value

Estimated Time

15 minutes

Skills Practiced

Prerequisites

• Addition: Add 2-Digit Numbers (No Regrouping)
• Place Value (Tens and Ones)

Next Steps

• Addition: Add 3-Digit Numbers (With Regrouping)
• Subtraction: Subtract 2-Digit Numbers (With Regrouping)