I had a Grange Hill binge a few months ago; that programme had some fantastic lines.
Mr Lewellyn (headmaster, to the anti-uniform activists): "I know who you are. Everyone in school knows who are. So, what can I do for you?"
"One thing you have yet to learn about me, is that I stick to my decisions."
Mr Baxter: "Before you hop it, mop it. Got it?"
Mr Mitchell (speaking like a teacher, to a police officer): "You mean Cathy doesn't even know if her own father is dead or not?"
Mr Bronson, to a crane operator: "But you're a woman!"
Crane operator: "Ten out of ten."
Mr Keating (just after the much-feared bully Stebson has thrown rice at someone): "Are you taking the part of a Chinese coolie, working in the rice fields? Every grain off the floor... NOW! And then, toddle along to my office."
"They (the headmistress) will only call a referendum when they're sure they'll get the result they want." Oh, the irony! (Sorry to bring that topic into a light-hearted thread.)