Teaching a cooking course

Please help. I'm a novice but am signed up to teach my first low fat cooking class at a local high school as part of the adult education program. I know what I wanted to make but here's the snafu...

they forgot to put a cap on enrollment and now I have 20 people vs. the 8 I had anticipated!!

Now, I'm in panic city as a novice.
Was planning on doing all hands on for those involved now it may be too much. Looking for input from those who have taught similar classes. Interested in your format, how much hands on you did and what went over best/worst.

Thank you soooooo much.