GeoGebra Math AppsGeoGebra is dynamic mathematics software for all levels of education that brings together geometry, algebra, spreadsheets, graphing, statistics and calculus in one easy-to-use package.
InstructablesClasses on various topics from 3D Printing to baking to IOT.
MIT OpenCouresewareMIT OpenCourseWare (OCW) is a web-based publication of virtually all MIT course content. OCW is open and available to the world and is a permanent MIT activity.
Udacity Ep: 245The main idea in this course is learning how to rapidly develop and test ideas by gathering massive amounts of customer and marketplace feedback.