Another aspect of school that seems so essential that you don’t even think about it, which is the fact that the different classes are based on age. What does that mean exactly? It means that normally kids in grade 7 are between 12 and 13, in grade 8 between 13 and 14 and so on. That is the natural order of things, it seems. When I see kids I don’t know, I’m pretty good at guessing which class there are in and then I can convert that into an age. Not the other way around. And it works because if you’re older or younger, you are an exception to the rule. Alright, you say, but where is the problem? Well, there is more than one.