PEMDAS and the Number-Gobbling Dragon

By Erica Simon, RME Project Specialist

In our digital world, creativity and a little storytelling can be a powerful mnemonic to understanding a basic principal of mathematics that all students need to be successful. Many students love to watch YouTube videos, and now, the new TED Ed site has organized these educational videos to allow teachers to find them and "flip" the videos into lessons. These videos are displayed on lesson pages already created with multiple-choice quizzes, open ended questions, and links to more information about the topic. A teacher can create her own lesson with any YouTube video by simply "flipping" it!

So how does this work? Let's look at a mathematics content example. PEDMAS – the well-known acronym for parenthesis, exponents, division, multiplication, addition and subtraction, is taught as students are introduced to problem solving strategies for equations and word problems. Although many a “trick” has been used to help students understand the order of operations, the clever folks at TED Ed(ucation) have used the power of animation and storytelling to deliver a swashbuckling tale of the Land of Pi where the numbers run wild. But only with the sequential attack of the mathematical symbols for the operations, are the numbers tamed and “order” is restored. Puff, the number-gobbling dragon is squashed by the symbolic musketeers who attack with precision and order to save the Land of Pi.



After students watch the video, there is a lesson already created if a teacher doesn't create her own. There are five multiple-choice questions and three open ended questions, including one where students must work to simplify an expression using PEMDAS. Last there are three resources where students can "dig deeper."

The IES Practice Guide for Problem Solving in Grades 4-8 provides recommendations that support procedural knowledge and flexibility as students develop skills to efficiently and correctly solve math problems. By tapping students’ prior knowledge of mathematical operations and supporting a solid understanding of the order in which operations are used, teachers help students become comfortable with symbols and correctly use them in their problem solving.

By sharing this whimsical approach to the order of operations with your class as a support for honing procedural knowledge, conceptual understanding and procedural flexibility, students will see mathematical rules come to life in a way that exemplifies why the order of operations matters when solving math problems.

Let us know what you think and how you could use TED Ed videos in your classroom.