The tools we were using, like Mathematica, are clunky, very expensive, and just don't do everything we need. And worst of all, they are closed source software, meaning that you can't even see how they work, and can't modify them to do what you really need. For teaching math, professors get bogged down scheduling computer labs and arranging for their students to buy and install expensive software.
So I started SageMath as an open source project at Harvard in 2004, to solve the problem that other math software is expensive, closed source, and limited in functionality, and to create a powerful tool for the students in my classes. It wasn't a project that was intended initially as something to be used by hundred of thousands of people. But as I got into the project and as more professors and students started contributing to the project, I could clearly see that these weren't just problems that pissed me off, they were problems that made everyone angry.
The scope of SageMath rapidly expanded. Our mission evolved to create a free open source serious competitor to Mathematica and similar closed software that the mathematics community was collective spending hundreds of millions of dollars on every year. After a decade of work by over 500 contributors, we made huge progress.
But installing SageMath was more difficult than ever. It was at that point that I decided I needed to do something so that this groundbreaking software that people desperately needed could be shared with the world.
So I created SageMathCloud, which is an extremely powerful web-based collaborative way for people to easily use SageMath and other open source software such as LaTeX, R, and Jupyter notebooks easily in their teaching and research. I created SageMathCloud based on nearly two decades of experience using math software in the classroom and online, at Harvard, UC San Diego, and University of Washington.
SageMathCloud is commercial grade, hosted in Google's cloud, and very large classes are using it heavily right now. It solves the installation problem by avoiding it altogether. It is entirely open source.
Open source is now ready to directly compete with Mathematica for use in the classroom. They told us we could never make something good enough for mass adoption, but we have made something even better. For the first time, we're making it possible for you to easily use Python and R in your teaching instead of Mathematica; these are industry standard mainstream open source programming languages with strong support from Google, Microsoft and other industry leaders. For the first time, we're making it possible for you to collaborate in real time and manage your course online using the same cutting edge software used by elite mathematicians at the best universities in the world.
A huge community in academia and in industry are all working together to make open source math software better at a breathtaking pace, and the traditional closed development model just can't keep up.