If you are curious about what an open class looks like in an EFL classroom in South Korea, then this might be helpful to you. But be aware! What you are about to see was rehearsed with the students and the activities weren't what we normally did day-to-day. Although, the open class wasn't "real" you can still get ideas for class management and group activities.
You have two options, you can watch the shorter or the longer version. I am posting the shorter one first.
The longer video is a fun 25 minutes long, and I won't be offended if you zipped through some parts.