Geometer's Sketchpad (GSP) is a computer program that one can use to investigate and create geometric constructions. This is a great classroom tool because it allows students to freedom to do such investigations quickly and accurately so that they can get a better grasp of geometric patterns and theorems.
One aspect of GSP that is especially useful is the ability to create "scripts" in the documents. These scripts, or tools, allow the user to save different processes that they have performed to use again. For example, if the cirmcumcenter of a triangle is constructed once, you can save the steps performed so that you do not have to reconstruct it again for another triangle.
In the GSP documnet, Scripts, I have created many tools for such constructions. Open the document and see what it has!