Surviving prison develops grit. Therefore it is beneficial to go to prison.

Counting the grains of sand on the beach develops grit. Therefore, it is beneficial to count the grains of sand on a beach.

Point: not all activities that develop grit are beneficial. The implication of the grit argument is that any tedious activity has some benefit - if not for anything else, then at least for the development of 'grit' itself. Which is a ridiculous argument; some tedious activities are tedious because they are pointless. A better lesson to learn is to spend your time wisely - on activities that are tedious for a reason.

So is school tedious for a reason? The answer is no, not really - but to prove that to you would likely take some time. I recommend you read up on John Taylor Gatto, which the speaker references above. See: http://www.cantrip.org/againstschool.html and http://www.cantrip.org/gatto.html