Desmos

Desmos encourages students to explore and discover equations by allowing anyone (most likely in middle school or older) to easily create and share rich, full color graphs, bringing the functionality of the old graphic calculator into the 21st century without the need for the actual calculator. Though the in-browser graphing software is its most well-known product, Desmos has also developed virtual whiteboard technology that will allow for the display of browser-based content on a variety of surfaces. Both services are free for students and teachers to use.

Desmos has its sights set beyond graphing and whiteboards, too. With funding from Google Ventures and others, Desmos is beginning to expand beyond this initial product by forming partnerships with textbook publishers (who will, presumably, make those textbooks more interactive and perhaps more open and shareable).