CS183B - Startup Class - Stanford class taught by Sam Altman & guest speakers
Alcamy - Free, open self-learning platform. Learn & teach anything.
YC Startup Class - A live, one-hour class by Sam Altman on Platzi
Stacks - A bookshelf for your online courses
Google Classroom - Learning management tool by Google
Airschool - Airschool is a live-streaming educational platform with engagement and monetization tools to help anyone start teaching online. It can be finance, business, wellness, meditation, branding, marketing; in short, anything you want!