We had a Chemistry teacher called Mr Shankra, we called him
Wanker Shankra. My pal crept up on him when he was writing on the black board and clipped a bunsen burner to his lab coat but when he felt the weight he grasped it and turned around at the metal bit smashed some test tubes on his desk.
Needless to say my pal got 6 of the belt and boy could Wanker Shankra draw the belt - his forearm swelled up like a balloon
happy days