The less scrupulous English language schools do exactly this where I live. They'll post a job offering online and have you teach a "demo class" as part of your

The less scrupulous English language schools do exactly this where I live. They'll post a job offering online and have you teach a "demo class" as part of your interview. In reality, that demo class is just a class that they didn't want to pay a substitute teacher for. Clever eh?