Elementary Math Lesson Plan: Calculating Percentages

Cash registers: they’re a coveted toy amongst children of all ages who want to scan items, handle cash, and use what they know about math to calculate discounts, sales, and merchandise totals. Just like house, playing store is an appealing game because it allows children to replicate the environment around them, practicing for their entrance into the real world. Teachers can leverage little kids’ love of make-believe shop keeping by giving students opportunities to practice the skills used in retail and sales. This week, we’re offering a lesson plan on calculating sales at the school store!

Whether you want to use copies of our print catalogue to allow students to select items to calculate discounts, or are interested in incorporating a technology component in your lesson plan by using our catalogue online, we have the resources you need to extend learning beyond the classroom.

Here’s the goal: to get students in grades 3-5 to apply what they’ve learned about percentages in a real world application. By converting common sales percentages – 10%, 25%, and 50% — to fractions and decimals, students will discover how to determine the price of an item when it is being offered on a discount. The following formulas can be used to help students calculate sale prices:

Price – (Price x Discount) = Sale Price

(1-Discount) x Price = Sale Price

We have a fun worksheet that students can complete collaboratively or independently to practice this skill – access it here. Using predetermined prices or by recruiting students to look up and find prices themselves, pupils can calculate the sale prices of items in the school store – and then apply what they’ve learned in the classroom as shopping becomes a part of their routine later in life.

For pre-and post- lesson activities, visit our website to see the comprehensive elementary lesson plan on calculating percentages, modeled around the curriculum standards of the National Council of Teachers of Mathematics and using methodologies from Bloom’s Taxonomy of Educational Objectives.


Lesson 1: What’s on Sale at the School Store?