National Council of Teachers of Mathematics
The Math Forum: Graphing Linear Equations
This site from The Math Forum provides chat areas, simulations, JAVAapplets, problems, answers, puzzles, quizzes and tutoring! Links are also provided for additional information.
Shodor Education Foundation
Shodor Interactivate: Lesson: Functions and the Vertical Line Test
This lesson plan outlines an activity that allows students to explore the vertical line test for functions.
Shodor Education Foundation
Shodor Interactivate: Lesson: Reading Graphs
Presents an introductory lesson to teach students how to read and plot graphs and determine functions based on graphs.
University of Vienna (Austria)
University of Vienna: Graph or Not Graph
Interactive quiz to determine whether each graph is representative of a function or not. Some graphs are discontinuous, some fail the vertical line test, and some actually are functions. After completion, the site gives a score to judge...