My second grade teacher taught us the civil war was because of a disagreement over state’s rights.

The same teacher marked me and a few other students down for completing a subtraction assignment using negative numbers. She explained we were supposed to be confused and write that we couldn’t do it.

Edit: I forgot one! My third grade teacher marked me down for not knowing how much a hen weighed. It wasn’t a joke. Apparently there was a rule of thumb for estimating chicken weight. Any kids who weren’t raised on a farm missed the question.