Area by counting squares: what children learn
In this game children find the area of rectangles and L-shapes drawn on squared paper, where each square is 1 cm². Counting in rows, rather than one square at a time, is quicker and more accurate.
Supports part of Common Core 3.MD.C.6: measuring areas by counting unit squares (square cm). This focused game does not cover the entire standard.
Common Core connection: 3.MD.C.6. This is focused practice for part of the standard.
How to play
Answer 10 questions before the clock runs out. Tap an answer, or press 1 to 4. Each game has 10 multiple-choice questions and a 150-second timer. A wrong answer shows the correct one before moving on. You earn up to three stars depending on your score.
Step by step
- Area means the space inside. It is measured in squares, written cm² for square centimeters.
- Count in rows. A rectangle 3 squares tall and 4 wide has 3 rows of 4: 12 squares.
- Split L-shapes. Split an L-shape into two rectangles, find each area and add them.
- Write the units. The answer is in square centimeters: 12 cm².
Worked examples
Example 1: A rectangle 3 squares tall and 4 wide. Each square is 1 cm².
Working: 3 rows of 4 = 12.
Answer: 12 cm²
Example 2: A rectangle 5 squares tall and 2 wide.
Working: 5 rows of 2 = 10.
Answer: 10 cm²
Example 3: An L-shape made of a 3 by 3 and a 3 by 2 rectangle.
Working: 9 + 6 = 15.
Answer: 15 cm²
Common mistakes and how to fix them
- Finding the perimeter instead of the area. Perimeter is the distance round the edge. Area is the squares inside.
- Counting some squares twice in an L-shape. Split the shape with a line and color each part.
- Writing cm instead of cm². Area is counted in squares, so the units are square units.
Activities to try at home
- Count the tiles on a floor or wall and work out the area in tiles.
- Draw shapes on squared paper and find their areas.
- Cover a book with sticky notes to measure its area.
Ideas for the classroom
- Students make rectilinear shapes on geoboards and find their areas.
- Give students 12 squares and ask how many different rectangles they can make.
- Compare two shapes with the same area but different perimeters.
Free printable game and worksheet
The free printable starts with a game sheet, such as a color-by-answer picture, an answer maze or a secret-code joke, followed by a worksheet. Both use the same checked questions as the online game, and the answers are on the last page. Print it, or save it as a PDF from your browser’s print menu.
Open the free printable game and worksheet
Frequently asked questions
How should I choose this game for my learner?
Supports part of Common Core 3.MD.C.6: measuring areas by counting unit squares (square cm). This focused game does not cover the entire standard.
What is a rectilinear shape?
A shape whose sides all meet at right angles, such as a rectangle or an L-shape.
Can it be played with a keyboard?
Yes. Press 1, 2, 3 or 4 to choose an answer.