Students will use calculators and manipulatives to explore what happens when they change one number at a time in an addition number sentence. They will observe and record the pattern that develops.

Students will explore the following concepts in this activity:

• whole numbers
• addition
• patterns

Have students read There Was an Old Lady Who Swallowed a Fly and write number sentences for this story.

Students will choose one of those number sentences and write it on their student activity sheets. Next, ask them to model the story they chose with manipulatives. Students will choose one number in the story to change, and then model the new number sentence. Students should continue to change the same number, recording and describing the pattern that develops.