In French language, arithmetic statements are often read, at the elementary school level, as , say, " deux et deux font quatre" , i.e. something like " two and two make four".
Out of this arises a belief according to which the $ \Large= $ symbol expresses some sort of action , either an action performed by numbers themselves or by the person that operates the mental activity of computation which is supposed to be denoted by the $\Large +$ sign.
This first belief may, in the head of older students, be replaced by the idea that $\Large =$ means " has the same magnitude " or " has the same value as".
I tried to show to high school students that the supposedly active meaning of $\Large =$ does not work anymore when the equality is reversed : $2+2$ may ( arguably) " make" $4$ , but would one say that $4$ " makes " $2+2$ ?
But I did no manage to convince them that, at least in the case of arithmetic statements, the " has the same magnitude " interpretation is not correct.
The identity meaning seems simply unbelievable to students.