What a perfectly flawless argument there! I cannot see anything wrong or anything questionable at all. Well done!

Music: Isn't this so you can play music by yourself?
Spanish: Dora the Explorer? Humans are better teachers than television shows.
English: Okay, so grammar means nothing. They're are very perfect reason in you're sentence.
History: Those who forget history are doomed to repeat it.
Math: How about when you don't have a calculator, or the calculator doesn't support the function you need?
Spelling: How about when spellcheck gives you multiple possibilities and you can't see which one it's supposed to be? How about when you can't use spellcheck? Also, spellcheck doesn't check grammar.