PhET Equation Grapher is effective and visual, adapting immediately to changes made in the equation, but it's weak in actual instruction. It will be a good tool for students who already have graphing knowledge to practice and extend, but it won't be good for graphing beginners looking to learn.
Use PhET's Equation Grapher in the classroom after instruction on graphing as a way for students to practice creating graphs for different situations. They can explore how changing variables affects the graph. You could also use it after a graphing assignment for students to check the graphs they created.Continue reading Show less
PhET Equation Grapher is a graphing simulator that lets students graph polynomials and see how changing the variable values affects the graphs. Students get started by simply going to the site and manipulating the variable values. Results are instantaneous. Students need prior knowledge of the subject matter to make sense of the data, but there's a brief instruction page on the tool's website to help users or teachers get started. This is also the place to find teaching ideas submitted by other teachers and to download versions in other languages (there are many).
The simulator is easy to use, and students can quickly change the data to observe the results. The more experience and instruction students have in graphing, the easier this will be to use.
For kids who have some experience with polynomials and graphing equations, the site will be very useful. They can explore the cause-and-effect relationships involved in changing one or more variable within an equation. Students can also graph up to two equations at a time for comparison. They can compare the equation as a whole to the corresponding equation for one term (when the other terms are zeroed out). It's also possible to graph linear equations by entering a value of zero for the appropriate terms.
However, students without previous knowledge or experience graphing equations will have a difficult time learning from the site. There's no direct instruction on how to use the tool within the simulator itself, so students have to figure out what changed as they make adjustments to the values. A helpful addition would be some basic explanation of how to graph polynomials that students could refer to when getting started. It would also be helpful if the graph allowed for a wider range of possible inputs, so students could graph larger values.