enVision Mathematics Grade 3, Topic 15: Attributes of Two-Dimensional Shapes
In this unit, your child describes and sorts flat shapes by their attributes, such as how many sides they have, whether sides are equal, and whether corners are square. They learn that quadrilaterals include rectangles, squares, and rhombuses, and split shapes into equal parts named as fractions. Next, they measure the distance around these shapes.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Topic 15?
- Grouping quadrilaterals, shapes with 4 straight sides, into rectangles, squares, and rhombuses, and drawing ones that fit none of those groups. Learn more: Sorting four-sided shapes into families
- Dividing a shape into parts with equal area and naming each part as a unit fraction, like 1/3. Learn more: Splitting shapes into equal parts
Sample questions to try together
These are real questions from our practice. Tap the speaker to hear one read aloud, or the light bulb for a hint, and talk about the answer together.
Question 1 of 3
Look at the shapes. They are all quadrilaterals. How many of them have 4 square corners?
- 2
- 3
- 1
How you can help
- Go on a four-sided-shape hunt in the kitchen, checking each corner with the corner of a sheet of paper to decide whether it is square.
- Make shapes with straws and ask your child to push a square into a rhombus, then talk about what stayed the same.
- Fold a sheet of paper into 3 equal strips and ask your child what fraction each strip is and how they know the parts are fair.
Where kids can get stuck
- Counting only rectangles and squares as quadrilaterals, leaving out shapes with four uneven sides.
- Splitting a shape into parts of different sizes and still calling each part 1/4.
- Thinking equal parts must look alike, so two halves with different shapes but the same area do not count.
Practice makes perfect
Bobby's Math Club has practice problems that adapt to your child’s level, each with a detailed explanation and an easy-to-follow video, so your child can build confidence in these skills one step at a time.
Words your child will hear
- quadrilateral
- Any closed shape with 4 straight sides.
- attribute
- A feature of a shape, such as its number of sides or its kind of corners.
- rhombus
- A four-sided shape with all sides equal, like a pushed-over square.
- rectangle
- A four-sided shape whose corners are all square corners.
- square
- A quadrilateral with 4 equal sides and 4 square corners.
- polygon
- A closed flat shape with straight sides.
- unit fraction
- A fraction with 1 on top, like 1/4, that names one equal part.
- equal area
- Parts that cover the same amount of space, even if they look different.
Want to help your child master two-dimensional shapes?
In Bobby's Math Club, your child practices these skills 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.
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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.
Which math standards does enVision Mathematics Grade 3 Topic 15 cover?
enVision Mathematics Grade 3 Topic 15 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
For teachers: Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence. Learn how Bobby's Math Club can help your students grow.