3rd Grade Identifying Trapezoids Worksheet: 5 Shapes to Check

A trapezoid is a shape with four sides, and two of those sides run side by side without ever meeting. This 3rd grade identifying trapezoids worksheet starts with a box that gives the rule. It says that a trapezoid is a quadrilateral with exactly one pair of parallel sides. Below the box, there are five shapes, labelled a to e. Some look like tables or roofs, one is a tilted square and one has five sides like a house. Next to each shape, your child checks Yes or No. The page sits on light grid paper, so the straight lines are easy to follow. Page two is the answer key, and it gives a short reason for every answer.

Five answers to check

The answers are yes for a and d, which each have exactly one pair of parallel sides. However, b is no, because the tilted square has two pairs. Item c is no as well, since the house shape has five sides and is not a quadrilateral. Finally, e is no, because none of its sides are parallel. All five answers in the key are right.

The rule box says "parallel side" where it should say "sides," and "four sided" needs a hyphen. In the key, "Because" has a capital letter in the middle of a sentence twice. This page uses the "exactly one pair" rule. Some US books also count a square as a trapezoid, so tell your child which rule their class uses.

At the table: finding parallel sides with two pencils

Give your child two pencils and ask them to lay one along each of two sides that could be parallel. If the pencils keep the same gap all the way along, those sides are parallel. Then your child counts the pairs. One pair means a trapezoid, while two pairs or none mean no.

Ask your child to count the sides first, too. If a shape does not have four sides, it is not a quadrilateral, so the answer is no straight away. That quick check settles item c before any pencils come out.

After the page: a trapezoid hunt at home

Look for trapezoids around the house, such as a lampshade seen from the side, a handbag or a bucket. First, your child names the parallel sides and shows them with two fingers. Then draw a rectangle on paper, and cut a straight line from one top corner to a point on the bottom side. The bigger piece is a trapezoid, because its top and bottom sides are still parallel. Finally, your child cuts the other top corner the same way and checks whether the shape is still a trapezoid.