On the subject of locking supply cupboards...
We had a new languages teacher in my school who was fresh from doing her teacher training in Germany. Now, I don't know if things are different in German schools, but her method tended to be a combination of repeating a scripted lesson and getting furious at my class, who had no interest in learning how to speak German at all.

She'd only been in my school for a month when she tried to give us the talk about the "Six secrets to speaking German." Unfortunately, due to her accent, she started the lesson off by saying, "Now listen, I have sex secrets..."

Cue instant attention from the class. "Really, miss?" "Ooh, tell us all about them miss!" Not realising she was being mocked, the teacher carried on, with every innocent comment about the throat muscles and exercising the voice box raising a chorus of nods. After a few minutes she caught on when one of the guys in my class stood up, sashayed over to her and said, "Oo miss, I have some sex secrets too, and I wanna tell you aallll about them."

She blinked, and without even speaking to him, dragged him off by the arm and locked him in the cupboard at the back of the room. Then she calmly returned to the front of the class and started handing out copy books. The rest of the lesson passed in silence, apart from the occasional THUD from the cupboard as our classmate tried to escape. After a while he gave up. Then the lesson ended, and we all went to lunch.

After lunch, in registration, our classmate was conspicuously absent. "Do you think he's been suspended?" We all asked each other. Nope- he was still locked in the cupboard. The teacher had forgotten that she'd locked him in, and gone off for her own lunch. He was rescued when the next class went in there, a good 3 hours after he was locked in.
(Sivvus trolley collision in the fruit aisle led to a jam, Thu 8 Sep 2011, 23:10, 3 replies)

I know of a teacher
who managed to lock himself in a cupboard, whilst trying to make a point to his class.
( monster munch person, man, woman... camera... TV?, Fri 9 Sep 2011, 10:43, closed)

Well, he certainly made A point
( scarpe We Stole Bikes, Fri 9 Sep 2011, 10:52, closed)

Hahaaaa!

(Sivvus trolley collision in the fruit aisle led to a jam, Fri 9 Sep 2011, 18:52, closed)