Pix has made a very good point. For myself, in Korea I have seen how Korean teachers teach. They teach for about 15 or 20 minutes and then give some activity for their students to do while they do other work (reports, internet shopping etc). I totally disagree with this as I think when you give the kids some activity then you should check them by walking around and listening in on their conversations. That's how you will know that what you have taught earlier has been productive.
Constantly we are always changing our teaching ideas and styles and one of the ways that we can find out how our lesson plans are going is by "listening in on the students." You can hear common mistakes and correct them with the entire class later rather than spending individual time, depending on how many students you have in a class.
It used to always annoy me when I would do this and my co worker would go and use the computer instead of dividing the class up - I take one half and her the other but it's hard to find good Korean co teachers
