This collection includes resources you may use when teaching this concept to your students. The key to abstraction is to be able to identify and filter out or ignore the details not necessary to solve the problem. From there, a model (equation, image, word, simulation, etc.) can be developed to represent all the important variables. A variable is a changing value that can be represented by a number, letter, word, blank, image, etc. Often, the value of one variable will determine, or be dependent upon, another. In these examples, you can see how the value of the second variable, or input, is dependent on the value of the first variable or input. Abstraction allows you to create a generic representation of a problem.