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How to Explain Fractions to Third Graders

Learn how to introduce fractions to 8 and 9 year olds. Discover concrete strategies for teaching equal parts, unit fractions, and comparing fractions that actually work.

Mathify Team

Mathify Team

Fractions are where math starts to feel different.

Whole numbers make sense: 3 apples, 7 books, 12 eggs. But half an apple? A third of a pizza? This is new territory for third graders—and often frustrating territory.

Here's how to make fractions click.

The Foundation: Equal Parts

Before anything else, your child needs to understand equal parts.

A fraction only makes sense when a whole is divided into equal pieces.

Show the Difference

Equal parts:

[    |    |    ]  ← Three equal parts. Each is 1/3.

Unequal parts:

[  |      |   ]  ← Three parts, but NOT equal. These aren't thirds!

Practice identifying equal parts in real life:

  • Is this pizza cut into equal slices?
  • Are these pieces of paper the same size?
  • Did we share the cookie equally?

Understanding Fraction Notation

A fraction has two numbers:

  1   ← Numerator (how many parts we have)
 ---
  4   ← Denominator (how many equal parts in the whole)

The Denominator Story

Denominator = how many equal parts the whole is cut into

If a pizza is cut into 8 equal slices:

  • The denominator is 8
  • Each slice is 1/8 of the pizza

If the same pizza were cut into 4 slices:

  • The denominator is 4
  • Each slice is 1/4 of the pizza

Key insight: The bigger the denominator, the smaller each piece.

  • 1/8 is smaller than 1/4 (more pieces = smaller pieces)

This is counterintuitive! Bigger number = smaller piece. Spend time on this.

The Numerator Story

Numerator = how many of those equal parts you have

If you eat 3 slices of a pizza cut into 8:

  • You ate 3/8 of the pizza

The numerator counts the pieces. Simple once the denominator makes sense.

Unit Fractions: The Building Blocks

A unit fraction has 1 as the numerator: 1/2, 1/3, 1/4, 1/5, 1/6...

These are incredibly important because:

Every fraction is made of unit fractions.

  • 3/4 = 1/4 + 1/4 + 1/4 (three fourths)
  • 2/3 = 1/3 + 1/3 (two thirds)
  • 5/8 = 1/8 + 1/8 + 1/8 + 1/8 + 1/8 (five eighths)

When your child understands unit fractions, they can understand any fraction.

Comparing Unit Fractions

Which is bigger: 1/3 or 1/6?

Visual approach:

1/3: [████|    |    ]   ← Whole divided into 3 parts
1/6: [██|  |  |  |  |  ] ← Same whole divided into 6 parts

1/3 is bigger because fewer cuts means bigger pieces.

The rule: With unit fractions, bigger denominator = smaller fraction.

  • 1/2 > 1/3 > 1/4 > 1/5 > 1/6...

Fractions of Shapes

Third graders work extensively with fractions of shapes.

Circles (Pizza/Pie Model)

    ___
   /   \
  | 1/4 |
   \___/

Easy to visualize, familiar from real life.

Rectangles (Chocolate Bar Model)

┌───┬───┬───┬───┐
│   │ X │ X │   │
└───┴───┴───┴───┘

2 out of 4 parts are shaded = 2/4

Great for connecting to arrays and area.

Number Lines

0         1/4        1/2        3/4         1
|----------|----------|----------|----------|

Number lines show fractions as positions, connecting to measurement. This is crucial for later math.

Comparing Fractions

Third graders learn to compare fractions in specific cases:

Same Denominator

Which is bigger: 2/5 or 4/5?

Same size pieces (fifths). Who has more pieces?

  • 2/5 = two fifths
  • 4/5 = four fifths
  • 4/5 > 2/5

Rule: Same denominator → compare numerators.

Same Numerator

Which is bigger: 2/3 or 2/6?

Same number of pieces. But what size are the pieces?

  • 2/3 = two thirds (larger pieces)
  • 2/6 = two sixths (smaller pieces)
  • 2/3 > 2/6

Rule: Same numerator → smaller denominator means bigger pieces, so bigger fraction.

Comparing to 1/2

Is 3/8 more or less than 1/2?

Half of 8 is 4. So 4/8 = 1/2.
3/8 is less than 4/8.
Therefore 3/8 < 1/2.

This benchmark strategy helps with many comparisons.

Equivalent Fractions

Two fractions can name the same amount:

1/2 = 2/4 = 3/6 = 4/8

Visual Proof

1/2: [████████|        ]

2/4: [████|████|    |    ]

4/8: [██|██|██|██|  |  |  |  ]

All show half the shape shaded.

The Pattern

Multiply both numerator and denominator by the same number:

1/2 × 2/2 = 2/4
1/2 × 3/3 = 3/6
1/2 × 4/4 = 4/8

Third grade introduces this concept; fourth grade develops it fully.

Fractions Greater Than 1

Third graders are introduced to fractions greater than 1:

5/4 means five fourths.

If one whole has 4 fourths, then 5/4 is:

  • One whole (4/4) plus one more fourth (1/4)
  • Written as the mixed number: 1 1/4
[████|████|████|████] [████|    |    |    ]
       1 whole        + 1/4 extra

Common Misconceptions (And How to Fix Them)

Misconception 1: Bigger Denominator = Bigger Fraction

Error: Thinking 1/8 > 1/4 because 8 > 4.

Fix: Always draw it. Show that 8 pieces from one pizza means smaller slices. Use the same-size whole!

Misconception 2: Adding Tops and Bottoms

Error: 1/2 + 1/3 = 2/5

Fix: Show with pictures that 1/2 + 1/3 is clearly more than 1/2, but 2/5 is less than 1/2. This doesn't work! (Proper addition of unlike fractions comes later.)

Misconception 3: Fractions Aren't Numbers

Signs: Child can shade 3/4 of a shape but can't place 3/4 on a number line.

Fix: Use number lines regularly. Fractions are numbers that live between whole numbers.

Misconception 4: Different Wholes

Error: Comparing 1/2 of a small pizza to 1/4 of a large pizza.

Fix: Emphasize: We can only compare fractions of the SAME whole. 1/2 > 1/4 when we're talking about the same pizza.

Hands-On Activities

Fraction Strips

Cut paper strips into halves, thirds, fourths, sixths, eighths.

Line them up:

  • How many fourths make a half?
  • Are 2/6 and 1/3 the same?
  • Which is bigger, 3/4 or 2/3?

Pattern Blocks

Yellow hexagon = 1 whole
Red trapezoid = 1/2
Blue rhombus = 1/3
Green triangle = 1/6

"How many triangles cover the hexagon?" (6)
"What fraction is one trapezoid?" (1/2)

Cooking

Recipes use fractions constantly:

  • "We need 1/2 cup of sugar."
  • "Cut this in thirds so we each get an equal piece."
  • "The recipe calls for 3/4 teaspoon."

Sharing Fairly

Real division creates fractions:

  • 1 cookie ÷ 2 people = 1/2 each
  • 3 brownies ÷ 4 people = 3/4 each
  • 2 sandwiches ÷ 3 people = 2/3 each

Fraction Vocabulary

Make sure your child knows:

  • Fraction: A number representing part of a whole
  • Numerator: Top number (how many parts)
  • Denominator: Bottom number (how many equal parts in the whole)
  • Unit fraction: Fraction with 1 as the numerator
  • Equivalent fractions: Different fractions naming the same amount
  • Whole: The entire thing being divided

Building Toward Fourth Grade

Third grade fraction work prepares students for:

  • Adding and subtracting fractions with same denominators
  • Multiplying fractions by whole numbers
  • Converting between fractions and decimals
  • More complex equivalence

A strong foundation now prevents fraction fear later.

The Bottom Line

Fractions require a different kind of number thinking. The key is always:

  1. Start concrete: Use real objects, drawings, manipulatives
  2. Equal parts: This is non-negotiable
  3. Connect representations: Same fraction shown as picture, number line, symbol
  4. Compare carefully: Same whole, different methods for different cases
  5. Build from unit fractions: All fractions are made from these building blocks

When your third grader looks at 3/4 and sees "three of the four equal pieces"—not just "3 over 4"—they have true fraction understanding.

Frequently Asked Questions

What fraction skills should third graders master?
Third graders should understand that fractions represent equal parts of a whole, identify unit fractions (1/2, 1/3, 1/4, etc.), understand that the denominator tells how many equal parts and the numerator tells how many parts we have, compare fractions with the same numerator or same denominator, and recognize equivalent fractions in simple cases.
Why do kids struggle with fractions?
Fractions require a shift in thinking from whole numbers. Bigger denominators mean smaller pieces (counterintuitive), comparing fractions doesn't work like comparing whole numbers, and the same fraction can look different (1/2 vs 2/4). Building strong visual understanding helps overcome these challenges.
What's a unit fraction and why does it matter?
A unit fraction has 1 as the numerator: 1/2, 1/3, 1/4, 1/5, etc. These are the building blocks of all fractions. 3/4 is three 1/4s. Understanding unit fractions makes all other fractions easier because you're just counting how many of those unit pieces you have.

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