Crossref - Crossref makes research outputs easy to find, cite, link, assess, and reuse. We’re a not-for-profit membership organization that exists to make scholarly communications better.
Teachable - Create and sell beautiful online courses with the platform used by the best online entrepreneurs to sell $100m+ to over 4 million students worldwide.
Academia.edu - Academia is a website where you can share papers that are written with other users. You can use a Google or Facebook account to sign in to the website.
Clever - syncing between education applications for K-12 schools
Cabri Express - Cabri Express is an all-in-one math toolkit that facilitates the teaching and learning of mathematics from hight school to university
Claroline - Claroline is a collaborative eLearning and eWorking platform.