There are 2 very good websites for maths in France : le matou matheux and sesamath.
Very good for teenagers to understand maths better and to practise.

Ouishare is a community that helps promote openness in many domains, including Education.

Moocstarter is a website where anyone can ask for a new kind of MOOC to be created. If the idea gets enough votes, they search for teachers and create it in different languages.

Go have a look at www.mooc.fr
It is created to talk about MOOCs and learn about new ones in french.

With Createspace, you can publish your own books without paying anything, you just have to create the cover, decide the price by adding your author rights to the costs of the book and decide where they will be available.

You can create free ebooks on KDP.

You can find all the courses on Académie en ligne.

You can find MOOCs on FUN, now in different languages.