Translation of words is often difficult because sometimes They Just Don't Say Things That Way (TM).

If in French you often refer to acts of naughtiness, in English correspondingly you talk about -being- naughty. 

In French you probably say somewhat translated "stop with all your bêtises", but in English you'd say "stop being naughty".

There is a literal translation, 'stupidities', but that is not really a recognized word in English. There is also the literal translation of 'small act of naughtiness' which is 'peccadillo' which is not really used for childish acts.