I'm glad they got caught. That will 'teach them a lesson'! [=they will learn that they should not do that again]
We 'learned our lesson' the hard way. [=we learned from an unpleasant experience]
They studied the 'lessons' [='teachings'] of the great philosophers.
(..) she should be moving in slow motion? Will she want a large wedding, you think? Shall we say swords? Pistols at dawn? Have you remembered nothing? Recall the lessons of Adam Smith... ...the father of modern economics. "In competition... "...individual ambition serves the common good." (..)2001 A Beautiful Mind