Thinking About Three-Digit Numbers

Introduction

• Write down the following numbers on the whiteboard: 179 and 468.
• Say, "Think about what you know about place value and discuss the following questions with an elbow partner." Write the question stems and corresponding sentence frames on the whiteboard and read them aloud:
  • Do these numbers have any similarities, or things that are the same?
    • These numbers are the same because ________.
  • Which number is the biggest? Which number is the smallest?
    • The biggest/smallest number is ________.
  • Imagine these numbers were on a number line. What number might be in between them?
    • The number ________ would be in between ________ and ________.
• Give students a few minutes to discuss their ideas with their peers. Allow a few students to share out and guide them to use the sentence frames for support. Do not correct their answers, simply allow students to share their thoughts without the pressure of being correct.
• Clarify that both numbers are three-digit numbers. Explain that three-digit numbers are numbers with a value in the ones place, a value in the tens place, and a value in the hundreds place. Read both numbers aloud and have students repeat the numbers chorally back to you (e.g. one hundred seventy nine).
• Explain to the students that today they will be comparing sets of three-digit numbers to gain a better understanding of what three-digit numbers are.