Teaching the rate of change over an interval as a property of various functions separates it from the study of the limit. It is suggested that the rate of change be taught in high school as part of the study of functions during pre‐calculus studies. Whenever a new function is introduced, its rate of change over a given interval will be computed and interpreted. Introduction of the rate of change into the pre‐calculus curriculum paves the way for proving theorems about the derivatives of the sum and product of two functions. An algebraic and a numerical approach to the computation of the rate of change are presented. The numerical approach is simple and easy to implement on a microcomputer. A computer program in BASIC which plots any given function, its rate of change function over an interval, and the rate of change at any given point, is provided.