Chapter 4 · Introduction to fractions (I)

Lesson 4.2 · Unit fractions (1)

Hua's Classroom for Shanghai Maths — One Lesson One Exercise (English edition, pages 81–82).

Grade 3 Second Semester Pages 81–82 ECNU Press

Lesson Alignment

How this Shanghai Maths lesson connects to learning goals, Common Core, and Eureka Math.

Learning Objectives

Students will be able to:

  1. 01Read and write unit fractions ($1/2$, $1/5$, $1/10$). (Question 1)
  2. 02Colour parts to match a unit fraction. (Question 2)
  3. 03Express shaded parts as unit fractions. (Question 3)

Common Core Standards

CodeStandard (focus for this lesson)
3.NF.A.1Unit fractions as equal parts of a whole.

Eureka Math Correspondence

Shanghai MathsFocusEureka Math
Unit fraction1/bG3 M5 Topic A

Core Concepts

Unit fractions: one equal part of a whole.

What is a Unit Fraction?

$\frac{1}{n}$ means 1 of $n$ equal parts.

Read & Write

Say “one fifth”; write $\frac{1}{5}$.

Colour the Part

Shade exactly one equal part of the whole.

Key Terms & Definitions (Reference)

Quick glossary for this lesson.

TermDefinition
Unit fractionA fraction with numerator 1.
DenominatorHow many equal parts the whole is divided into.

Key Answers

Quick reference for this lesson’s exercise answers.

1. Read and write

  1. $\frac{1}{4}$: one fourth;\; $\frac{1}{50}$: one fiftieth.
  2. One fifth $\frac{1}{5}$; one third $\frac{1}{3}$.
  3. One tenth $\frac{1}{10}$; whole divided into $10$ equal parts; each is $\frac{1}{10}$.

2. Equally divided?

✓, ✕, ✕, ✕, ✓

3. Shaded parts

$\frac{1}{8}$;\; $\frac{1}{4}$;\; $\frac{1}{3}$.

4. Colour / circle

Shade/circle $1$ of $8$; $1$ of $3$ stars; $1$ of $4$ triangles.

5. Unit fractions

$\frac{1}{2}$;\; $\frac{1}{6}$;\; $\frac{1}{3}$;\; $\frac{1}{4}$.

6–8. Enhancement

  • Class size example: $15$ pupils; you $\frac{1}{15}$; girls $\frac{6}{15}$ (use your class).
  • Two days: $\frac{1}{2}+\frac{1}{4}=\frac{3}{4}$ of the book.
  • Folded $3$ times → $8$ equal parts; each is one eighth $= \frac{1}{8}$.