Sorry to say that is the drawback of all classes. In pre-k. children come home and tell parents their training is wrong because teacher so&so said to do it that way. My grandmother always said it takes a newly baptised person a year to calm down and realize everyone falls short of the mark of perfection. You were wise to point her towards this site. She may learn if it works for a project, no one cares how it is done.
Hang in there she will calm down.