# Lesson 5: Comparing Big Numbers

## Getting Started

### Questions to Explore

• How does place value work?
• How can we use place value to name, create, and compare numbers to a million?
• How do we write and speak in mathematical language?

### Skills

• Read and write multi-digit whole numbers using base-ten numerals, number names, and expanded form
• Compare two multi-digit numbers based on meanings of the digits in each place, using >, =, and < symbols to record the results of comparisons

### Materials

• fine point dry-erase markers (kit)
• laminated place value chart (kit)
• M&Ms
• small baggies (2)

### Introduction

Materials: fine point dry-erase markers (kit), laminated place value chart (kit), M&Ms, small baggies (2)
To review comparing multi-digit numbers and practice using the =, <, and > signs, have your child play the interactive game at the following web link.
To prepare for the next activity, while your child plays the game, make two small baggies of M&Ms with the following colors and numbers of candies:
• Bag #1: 1 brown, 4 yellow, 7 red, 4 orange, 1 green, 2 blue
• Bag #2: 1 brown, 4 yellow, 3 red, 9 orange, 8 green, 6 blue
Once your child has had about five minutes to compare and order a range of numbers in the previous game, pose the following questions:
• If you're comparing two three-digit numbers, how do you know which one is greater? (the one with the higher digit in the hundreds place is greater)
• Can you use the same approach when comparing four-digit numbers? How? (yes, you look at digits in the thousands place)
• What if you're comparing two four-digit numbers and they have the same digit in the thousands place? (then you look at the digits in the hundreds place)
Make sure that your child understands that he should begin comparing numbers by counting the number of digits in each number. Next, if the numbers have the same numbers of digits, he should look at the digits in the largest places (the places on the left end) first. If those digits are the same, then he should look to the next smaller place. If those digits are also the same, he should then look to the next smaller place, and so on.

Give your child the laminated place value mat and dry-erase markers. He will write the following numbers in the rows provided on the mat as you dictate them:
• one million three hundred sixty-six thousand four hundred thirty-two (1,366,432)
• two million one hundred eighty-seven thousand one hundred twenty-two (2,187,122)
• one million four hundred sixty-five thousand two hundred sixty-two (1,465,262)
Now, pose the following questions as your child looks at the numbers:
• Which is the greatest number? (2,187,122)
• How do you know? (it has 2 in the millions place and the other numbers have only 1 in the millions place, it has more millions than the other numbers)
• Of the remaining numbers, which is the greatest? (1,465,262)
• How do you know? (it has more hundred thousands than the other number)