After our stratigraphy studies we move on to faults. I love telling them about left (sinistral) and right (dextral) lateral faults and the origins of the terms. Students build their own small models that they can manipulate to show normal, reverse, lateral, and oblique faults. They can easily see if the land lengthens or shortens and therefore what type of forces might cause the faulting. I always ask what happens to the river when flowing SW and there is a normal fault and it gives me a chance to say, “what did the fish say when it swam into the concrete wall? . . . . .