Freebee Friday: Graph-Tastic
Who needs graphing calculators if you have a classroom of notebook computers. You’ll need a graphing and analysis program like Geo-Gebra, but it's free and you can distribute it to students as long as you don’t change or charge for it. While it’s not as powerful a math-teaching tool as Sage, Geo-Gebra is my favorite for doing math on a PC because it’s a lot simpler to use and you won’t spend a full class explain how to do things with it. Kids (and some teachers) just get it.
The program is good for elementary through high school classes, runs on Java and is easy to set up and use. There's a lot of classroom material and it's a quick starter. For instance, need a circle? Just grab it from the Menu bar and plop it where it needs to be and resize it. As you do this the code to create it is automatically placed on the left side so you can tweak it if you need to. A big bonus is that curious advanced student will no doubt use this as a way to teach themselveds how to progam in this language.
Depending on what you’re doing, you can use a grid background or not and every operationcan be undone. I really like the software's Wiki page, which has a good primer on how to use Geo-Gebra along with some classroom learning materials, including article, applets and classroom activities. The best part is that it will run on just about every computer in your school, including Windows, Mac and many Linux variants.