The confusing part is (here in the states), all the kids do actually learn the Metric system in their grade school science classes, starting in elementary schoo

The confusing part is (here in the states), all the kids do actually learn the Metric system in their grade school science classes, starting in elementary school (primary, I think they call it elsewhere). Everyone I know knows the Metric system, but they give me queer looks when I use it, e.g. in conversation. Not like it's insulting their American-ness or something either; I really don't get it. It's worst with temperature, where people have to fight their training to estimate the temperature in Fahrenheit.