Counting squares to measure area

Mathematics · Measurement · ages 8-9

Name ______________________ Date ____________

A book cover is tiled with square centimetre tiles: 3 rows of 4. What is its area in square centimetres?
Answer: ______________
An L-shape covers 8 full unit squares. What is its area?
- 8 square units
- 8 units long
- 4 square units
- 16 square units
Which one describes a unit square used to measure area?
- A small square used to measure area, and every one is the same size
- Any square you draw, no matter how big or small
- A four-sided shape where every side is a different length
You can find the area of a shape by counting the unit squares that cover it.
Circle one: True False
A cover is 6 tiles long and 4 tiles wide. How many tiles cover it?
Answer: ______________
Shape A is covered by 14 unit squares. Shape B is covered by 11 unit squares. Which shape has the bigger area?
- Shape A
- Shape B
- They are the same
An L-shape splits into a 4 by 2 rectangle and a 2 by 2 square. What is its total area?
- 8 square units
- 10 square units
- 16 square units
- 12 square units
Lila counts only whole squares and ignores half squares, getting 8 for a shape that truly covers 10. Her teacher says she undercounted. Is the teacher right?
Circle one: True False
Ravi counts the unit squares inside a shape but skips every square that is only half covered. Is his area measurement correct?
- No, it will be too small because those half squares still cover some space
- Yes, only whole squares should ever be counted
- No, it will be too big because he added extra squares
An L-shape is made of a 5 by 3 rectangle plus a 2 by 3 rectangle. What is its total area?
Answer: ______________

Answer key

For grown-ups. Fold this page away before handing over the rest.

Counting squares to measure area W1-mt_y1n0Zwhoca-s1

12 · The area is 12 square centimetres because 3 x 4 = 12.
8 square units · 8 square units is correct because area counts the covering squares. 8 units long is a length, and 4 or 16 miscount the cover.
A small square used to measure area, and every one is the same size · Unit squares must all be exactly the same size, so each one you count adds exactly one square unit.
True · That is exactly how area is measured: cover the shape with unit squares and count them.
24 · 24 tiles because 6 x 4 = 24.
Shape A · More unit squares means a bigger area, so Shape A is bigger even if it looks smaller on the page.
12 square units · 12 square units is correct because 4 x 2 = 8 and 2 x 2 = 4, and 8 + 4 = 12.
True · The teacher is right because skipped halves still cover space: two halves make a whole that Lila missed.
No, it will be too small because those half squares still cover some space · Half-covered squares still take up part of the shape, so skipping them makes the total too small. Count them as a sensible estimate instead.
21 · The total is 21 because 5 x 3 = 15 and 2 x 3 = 6, and 15 + 6 = 21.