3rd Grade · Measurement & Data
3.MD.C.5: Understand area: how many squares it takes to cover a flat shape
3.MD.C.5 is a 3rd grade Common Core math standard in Measurement & Data. Here’s what it really covers, and how you can help your students learn it.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
The standard
Recognize area as an attribute of plane figures and understand concepts of area measurement. a. A square with side length 1 unit, called "a unit square," is said to have "one square unit" of area, and can be used to measure area. b. A plane figure which can be covered without gaps or overlaps by n unit squares is said to have an area of n square units.
In plain words
Understand area: how many squares it takes to cover a flat shape.
Sample questions from student practice
These questions from Bobby's Math Club are the kinds of questions your students will see. You can try answering them to see what a student might see.
Question 1 of 3
You want to cover a rectangular garden with new grass. Which measurement tells you how much grass you need?
- Perimeter
- Length
- Area
Where students can get stuck
- Leaving gaps or overlapping tiles when covering a shape, then counting anyway, so the area comes out wrong.
- Confusing area with perimeter, counting unit lengths along the edges instead of the space inside.
- Thinking shapes with different outlines cannot share an area, though a long strip and a square can both cover 16 squares.
Effective teaching strategies
- Cover shapes with square tiles, with no gaps or overlaps, and ask students what the tiles measure.
- Show two different shapes covered by the same number of squares, so students see that different outlines can share an area.
- Trace the edge of a shape in one color and cover the inside in another, and ask which one is the area and which is the distance around.
Units that teach this standard
Find where 3.MD.C.5 lands in the program you teach. Each unit has a guide written for families. Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence.
Bridges in Mathematics
enVision Mathematics
Eureka Math
Eureka Math²
Everyday Mathematics
i-Ready Classroom Mathematics
Illustrative Mathematics
Math Expressions
Reveal Math
Zearn Math
Don’t see your curriculum? Contact Bobby and we’ll see if we can help!
Share it with families
Families can read Area: how much flat space a shape covers for a plain-language look at this skill, with three questions to try together and ideas for helping at home.
Help every student practice measurement and data at home
In Bobby's Math Club, students practice at just the right level, with a hint when they need one, a clear explanation after every question, and kid-friendly videos. Unlimited practice is free for every family.
See how it works for teachers
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.