J'ai eu 18 en maths, je n'ai pas menti

How does the French grading system out of 20 work?

French schools mark out of twenty. Une note sur 20 is a score, la moyenne is ten — the usual pass line and halfway mark — and anything from about sixteen upwards is uncommon enough that pupils announce it. So j’ai eu 18 en maths is a far bigger claim than “18” sounds to anyone raised on percentages, which is why it is worth bragging about, or lying about.

La moyenne does double duty, and that is the word to learn alongside the scale. It is the ten-out- of-twenty pass mark, so avoir la moyenne means “to pass”; it is also your average across a subject or a term, as in la moyenne générale. Être au-dessus de la moyenne therefore works both ways — above the pass, or above the class.