Teach by Mozilla is described as 'We want more people to see themselves as citizens of the web. The Mozilla Learning Network offers programs and a global community dedicated to helping people learn the most important skills of our age: the ability to read, write and participate in the digital world' and is an website. There are three alternatives to Teach by Mozilla, not only websites but also apps for Android and Windows Phone. The best Teach by Mozilla alternative is Instructables. It's not free, so if you're looking for a free alternative, you could try Instructables or Hackr.io.