Chapter 6 · Consolidation and enhancement

Lesson 6.7 · How large are they

Hua's Classroom for Shanghai Maths — One Lesson One Exercise (English edition).

Grade 3First Semester Review 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. 01Find areas by counting grid squares in $\text{cm}^2$.
  2. 02Use length/width relationships between rectangles.
  3. 03Reason about larger/smaller rectangles from clues.

Common Core Standards

CodeStandard (focus for this lesson)
3.MD.C.5–7Area concepts and rectangle area.
3.MD.A.2*(related)* Measure/solve with units.

Eureka Math Correspondence

Shanghai MathsFocusEureka Math
AreaCount & relateG3 M4

Core Concepts

Area sense on grids — count and relate two rectangles.

Count Grid Squares

How many squares? How many square centimetres?

Rectangle Clues

Compare a larger and smaller rectangle using given side relationships.

Compare Rectangles

Fill missing length/width in metres from diagram labels.

Key Terms & Definitions (Reference)

Quick glossary for this lesson.

TermDefinition
Grid squareUnit used to measure area on paper.
Square centimetre$1\ \text{cm}\times1\ \text{cm}$ area.

Key Answers

Quick reference for this lesson’s exercise answers.

Key answers
  1. Grid areas: (1) $15$ cm²;\; (2) $21$ cm²;\; (3) $6$ cm²;\; (4) $11$ cm²
  2. Compound figures: (1) $41$ cm²;\; (2) $68$ cm²
  3. Square → rectangle: side $5$ m, area $25$ m²; increased by $10$ m²; smaller rectangle $5$ m by $2$ m; larger $7$ m long, area $35$ m²
  4. Two offices: larger $42$ m²; smaller $28$ m²
  5. Four rectangles: $?=500$ cm²
  6. Squares A & B: A $144$ cm²; B $81$ cm²