Is there a society right now that don't prioritized education for kids? If there is one then it's not a mandatory. But we have learn throughout history that education is very important. It is something that we can give to our children so that they will have a good life.
Whatever the arguments against education though, it just boils down to one factor, it is the only thing that we can partake to our kids sort of inheritance to have them schooled even if we parents didn't have one. And because we don't like our children to be like one of us who don't have formal education and makes our lives very hard to get a decent job because every company is looking for diploma and what you have finished in school.