## Lesson: Two-Digit Addition With Regrouping

Introducing the Concept

Children will use the Make a Ten strategy in this lesson, along with other strategies. Remind children that if they are adding two numbers such as 8 + 5, they can regroup the numbers to make adding easier. Tell children that they can take 2 from the 5 and add the 2 to 8 to make a ten. Also remind them that they must remember to subtract the 2 from the 5, leaving a 3, so they add 10 and 3 and get 13. Tell children that they will use this strategy to add two-digit numbers.

**Materials:** overhead projector, ten-frames and counters, tens and ones workmat, bundles of 10 craft sticks and single sticks, large number line, and large hundred chart

**Preparation:** Prepare a tens and ones workmat and a ten frame for use on the overhead. Make 9 bundles of craft sticks, 10 per bundle, using rubber bands to hold them together. Or use tens and ones blocks. Make a large number line and hundred chart for the classroom.

**Prerequisite Skills and Concepts:** Children should know the addition facts to 20 and the strategies used in learning them.