There are some consulates who don't take this very seriously at all.
Expect questions like
- Why do you want to go to Korea?
- Have you ever had a criminal record?
- Have you ever done drugs?
- What is your degree in? Why did you get that degree?
- How do you think you will be a good teacher?
- What is your teaching philosophy?
It approximately takes 10~15mins. The consulate is usually laid back about the interview and will be brief so go into the interview with a comfortable mindset.