Graphing functions can be a very tedious part of math curriculum, so the use of graphing calculators as a tool for instruction and discovery can be very beneficial. Graphing calculators allow students to see these visual representations without having to construct a graph by hand. This allows students more time to analyze and interpret their graphs.
The large screen that is part of a graphing calculator is also very beneficial because it allows the student to have multiple calculations on the screen to compare and contrast information. The graphing calculator can be used to generate lists of information and most have a randomization feature that help in this creation of lists.
The following websites contain resources for using graphing calculators
Graphing Calculator Tutorial