* class are copyrighted to the teacher (or the school) in many crountries, you might have some law problems. * students are generally poor => free to use * students are genereally technology addict and know how to configure ads blockers. * be sponsored by universities
Ideas : * allow teacher to subscribe, and have a different interface to answer students' questions (students may discuss without teacher know, of course) * mobile app to study in transport * allow teacher to add optional exercice with correction (you do not want to be another online school and allows teacher grades their students)
We can all theorize. Unplug and go find out (talk to them, face to face) if the students feel the pain.