I am running a startup that is a market place, http://greensprout.co for afterschool programs and summer camp providers (limited to Bay area). Naturally I am interested in this space. As a Korean, it is great to see startups working from Korea. The coding school is getting popular. So, it is a good place to start. But, there are many varieties. This seems to me like a tutoring service for computer programming. As you said it is video chat, is there youtube video to introduce the service? That will be helpful.

I have one kid, who is at your target. But I am not sure if I need tutoring like for block programming. I am more interested in real programming. Also, it is not clear what you will achieve at the end.

But, keep doing the good work since you have traction and I guess that people like the teaching quality, which you need to keep it consistent.