I'm still bitter about this. When I think of all the adults who told me that school really mattered when they must have known it didn't, it makes me mad. I worked hard in school. I worried endlessly about passing those exams. I did really well, then emerged into the adult world and found that 14 years of work meant absolutely nothing to anyone. I felt robbed of my childhood. I still do.
One of the lesser reasons I don't have kids is that. You have to tell them it matters, but you know it doesn't, most of the time. I'd really struggle with that.