This is a free web based coding platform suitable for grades 3 and up. Students are able to sign in to the site using their Google credentials (this allows progress to be saved but is not required.)
MakeCode provides many tutorials for its various tools including game design and programming a micro:bit.
Code.org provides a comprehensive coding curriculum for grades K-8. Teachers can register and create a class utilizing Clever. There is are teacher resources available through the site.
Students can login and move through the curriculum with some guidance from teacher. Throughout the coding tutorials are videos explaining key concepts as well as unplugged challenges.