Based on my experience
I created a tutorial site
This site is dedicated to students, and I announced on Facebook that I need teachers to answer questions.
Of course, these teachers will be given money for each set of points they collect (less than the cost of advertising).
This method has prompted the educators themselves to bring more students to increase the questions to increase the answers and thus increase their points.
Today's daily traffic is quite a good amount of hits via Google.
The site was created five months ago