Take seven eggs and boil six of them. Leave one raw. Get seven boys to stand in a row. Tell them that six of the eggs are boiled and one’s raw. See how much they trust their friends. Have each boy, one by one, break the egg over the guy’s head to his left. When you get to the end, make sure that boy #6 has the raw one! That way the last boy gets raw egg all over him and nobody gets chased. Then you can talk about either drugs or premarital sex or whatever and how much of a gamble it is, how you trust your friends but you never know when something is going to backfire on you like getting pregnant or an STD or getting in a car crash or overdosing.