Why does this need explaining?
Without school, we'd be plummeted back into a dark era, things would fall apart.
It provides both interesting and essential knowledge for the development of a person's intellect, and allows them to proceed and prosper in life. So it teaches some useless stuff as well, but the benefits outweigh the cons by several thousand tonnes, so to speak.
Jobs and careers these days are very demanding, and need academically and intellectually intelligent people to fulfill.
The benefits are very clear, ones which i don't feel its justified to spend my time explaining.