At the sea scouts, we used a fender with a weight on one end. It would be unexpectedly be thrown overboard, and everybody was supposed to react immediately: yel

At the sea scouts, we used a fender with a weight on one end. It would be unexpectedly be thrown overboard, and everybody was supposed to react immediately: yell "man overboard", have someone point, shout "swim!" at the man overboard (because sometimes they forget), and sail a certain pattern in order to arrive at the man overboard at a controlled course. We practices that dozens if not hundreds of times.