Geometry in third grade introduces kids to the idea that shapes have different categories (rectangles, rhombuses, etc..) attributes (four-sided, etc...) and areas of different values. This lesson, designed by our curriculum experts, provides the guided instruction and practice that third graders need to conceptualize shapes in a deeper way. For more practice, download and print the third grade geometry worksheets recommended as part of this lesson.
Your students will become junior math detectives as they hunt down the missing side of a rectangle by applying the area formula for rectangles. The only clues they have are the rectangle's area and the measure of one side.
Let’s give them something to talk about! Use this resource with your students to facilitate meaningful interactions between partners by giving each one different pieces of necessary information to find the area of a shape.
Area is a very important geometry concept that students learn around fourth grade. The area of a rectangle is one of the first areas that students learn how to calculate and measures how much space a rectangular shape takes up. Dive into our educational resources and master the concept of the area of rectangles or learn more about area here.
A Guide to Area of Rectangles
Area is defined as the amount of space an object takes up. A rectangle is one of the easiest shapes to work with, so we’ve put together a little guide on how to calculate the area of a rectangle.
The formula for a rectangle is the length of the rectangle times its width: A = L × W. If there is a rectangle with a length of 2 units and a width of 4 units, its area would be 2 × 4 = 8 units.
A square is a special type of rectangle that has four sides of equal length. Keep in mind, however, that while every square is a rectangle, not every rectangle is a square. The formula for the area of a square is the same for other rectangles, but since its length and width will be the same, we can also say that A = s2, or A = s × s, where s is the length of one of the sides.
To get more practice in finding the area of rectangles, check out our various resources on this page, or learn how to find the perimeter of a rectangle instead.