Building a bottom up online education marketplace with TinyPay.Me — from Kirsten Winkler
Quoting Kirsten:

Now, I could imagine two use cases for online education. One would be a marketplace for lesson material, lesson plans, tests, exercises etc. hence a more teacher targeting approach. As there are already some websites out there where teachers can sell their material to other teachers I am pretty sure that there is a growing market for that. You could either build something based upon age groups as verticals or subject matters, there are a lot of possible combinations.

The second opportunity I see is a marketplace for live online lessons. As you can sell virtual goods via TinyPay.Me teachers could offer individual lessons or lesson packages just like on the marketplaces and platforms we all know. The interesting part here would be that the marketplace itself would not interfere with the actual teaching part. Student and teacher would sort out where, when and how to meet on their own.