It is a great mathematical software for children from third grade through college. Students get better understanding of some abstract things about math. There is a section you can try it free and get a feeling of it. Students can start making sense by making connection between numeric and graphic representations.
To get sketchpad non expiring license you need to pay$70 for 1-4 computers, but it gets cheaper as more computers are added. There are free webinars. There are also workshops and courses they offer.
Ivan Sutherland, The American computer scientist and Internet pioneer has received the Turing Award from the Association for Computing Machinery in 1988 for his invention of Sketchpad, an early predecessor to the sort of graphical user interface that has become ubiquitous in personal computers today.
Welcome to The Geometer's Sketchpad® Resource Center This Resource Center supports users of the award-winning Dynamic Geometry® mathematics visualization software, The Geometer's Sketchpad.