How to Find the Rule in Input and Output Tables

Math with Mr. J

In this instructional math video, "Mr. J" provides a clear, step-by-step tutorial on solving input and output tables, also known as function tables. The video systematically covers four distinct examples, each corresponding to one of the basic operations: subtraction, multiplication, addition, and division. Using a digital blackboard format, the narrator demonstrates how to analyze the relationship between input and output numbers to determine the underlying rule. The content focuses on developing algebraic thinking by teaching students to identify patterns. A key theme is the strategy of determining whether values are increasing or decreasing to narrow down possible operations. For instance, the video explicitly models the process of trial and error—testing an addition rule first, realizing it fails for subsequent rows, and then correctly identifying a multiplication rule. It also addresses different table formats, showing both horizontal and vertical orientations. This video is an excellent resource for upper elementary classrooms introducing functions and patterns. It provides a solid model for "checking your work," as the narrator emphasizes that a rule must apply to every pair in the table, not just the first one. Teachers can use this video to introduce the concept of function rules, reinforce mental math strategies, or as a review tool for students struggling to distinguish between additive and multiplicative patterns.