That is an interesting idea. Here in Japan there would be a problem with the students being required to post in a public space. The privacy rules for students can be pretty complicated to navigate, especially for those in the secondary school system. Higher ed is a little more flexible, but not much.
That said, I will be thinking about this idea quite a bit before the next semester starts!
That is strange. Yeah... Laws in China have to be extremely different! My cousin actually lived there to intern for a bank to trade stocks and options. It would definitely work in college (if you made it optional). I was thinking I could test it for higher level students (like my Advance Computer Science class).