2.NBT.1.b: Numbers 100-900 as Hundreds, Tens, and Ones

I can understand that the numbers 100, 200, 300, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds (and 0 tens and 0 ones).

What Your Child Needs to Know

This standard focuses on helping your child understand that numbers like 100, 200, 300, etc., represent specific quantities of hundreds with no tens or ones. For example, 300 means 3 hundreds, 0 tens, and 0 ones.

Understanding these multiples of 100 is essential for working with three-digit numbers and builds on your child's previous work with place value. This concept helps students see the pattern in our number system and prepares them for working with larger numbers in future grades.

Real World Practice

Visual models and hands-on activities

Visual Models

1. Base-Ten Blocks

Use flat hundreds blocks to represent numbers like 300 (3 hundred blocks) or 700 (7 hundred blocks) with no tens or ones.

2. Place Value Chart

Create a chart with columns labeled "Hundreds," "Tens," and "Ones" and show how numbers like 400 have 4 in the hundreds place and 0 in both the tens and ones places.

3. Number Cards

Make cards showing the digit and its place value (e.g., 5 hundreds, 0 tens, 0 ones) to represent numbers like 500.

4. Hundred Squares Grid

Use grids where each grid represents 100, so 600 would be shown as 6 complete hundred grids.

Everyday Activities

1. Money Counting

Use dollar bills to represent hundreds (e.g., 4 dollar bills represent 400 cents) to help visualize multiples of 100.

2. Building Block Towers

Build towers where each level represents 100, then count by hundreds to find the total (e.g., a 5-level tower equals 500).

3. Number Hunt

Look for multiples of 100 in everyday life (page numbers, house numbers, prices) and discuss how many hundreds they represent.

4. Skip Counting by Hundreds

Practice counting by hundreds (100, 200, 300...) while doing everyday activities like climbing stairs or bouncing a ball.

Quick Checks

Strategies and quick activities

Strategies When Your Child Struggles

1. Use Concrete Objects First

Start with physical objects like base-ten blocks to represent hundreds before moving to abstract numbers.

2. Connect to Counting by Hundreds

Practice counting by hundreds (100, 200, 300...) to reinforce the pattern of multiples of 100.

3. Use Place Value Language

Consistently use terms like "3 hundreds, 0 tens, 0 ones" when talking about numbers like 300.

4. Make Real-Life Connections

Point out examples of multiples of 100 in everyday life, such as dollar bills or page numbers.

5. Create Visual Supports

Post a hundreds chart or place value chart in your home as a reference tool.

5-Minute Practice Activities

Activity 1: Hundreds Detective

Say a multiple of 100 (like 600) and ask your child to tell you how many hundreds it represents (6 hundreds).

Activity 2: Place Value Sort

Write various three-digit numbers on cards and have your child identify which ones are exact hundreds (100, 200, etc.).

Activity 3: Expanded Form Practice

Have your child write multiples of 100 in expanded form (e.g., 700 = 7 hundreds + 0 tens + 0 ones).

Activity 4: Hundred Hop

Call out a multiple of 100 and have your child hop that many hundreds from 0 on a number line (e.g., for 400, hop from 0 to 100, 200, 300, 400).

Check Progress

Track improvement

By the middle of the year, your child should:

  • Recognize that numbers like 300 represent 3 hundreds with no tens or ones
  • Count by hundreds to 900
  • Read and write multiples of 100 up to 900
  • Represent multiples of 100 using base-ten blocks or drawings

By the end of the year, your child should:

  • Fluently identify how many hundreds are in any multiple of 100 up to 900
  • Explain that in numbers like 300, the 3 represents 3 hundreds, not just 3
  • Understand that multiples of 100 have 0 tens and 0 ones
  • Apply this understanding when working with three-digit numbers

Mastery Signs

Your child understands this concept when they can:

  • Correctly identify the value of digits in multiples of 100
  • Write multiples of 100 in expanded form (e.g., 500 = 5 hundreds + 0 tens + 0 ones)
  • Explain why numbers like 400 are called "four hundred" (because they contain 4 hundreds)
  • Compare multiples of 100 based on the number of hundreds
  • Apply this understanding when adding and subtracting multiples of 100

Differentiation

Support for all learning levels

Below Grade Level

Practice problems focusing on counting by hundreds and identifying how many hundreds are in multiples of 100.

Download Practice Worksheet

At Grade Level

Standard practice with identifying and representing multiples of 100 as specific numbers of hundreds with 0 tens and 0 ones.

Download Grade Level Worksheet

Above Grade Level

Advanced practice applying understanding of multiples of 100 to solve problems with larger numbers and exploring patterns in our number system.

Download Challenge Worksheet