[waixingren]

The most difficult question to answer that you asked: "How would you advise I teach 20 some students all at different areas of experience with English?"

Ideally, you'd have them all separated into levels. Unfortunately, this rarely happens. One of the methods you could use would be to have the higher level students helping you. Provide the classes with conversation topics to practice speaking with each other--that way the better students can help out the others. Note: this method only works in some classes, it can depend on the differences in levels.