Getting an A or B is just a measure of your ability to memorize, not how well you actually apply the memorized content. A degree doesn’t entitle you to a job, for the same reason that, knowing how to use Illustrator doesn’t make you an artist. Your teachers are human, so they’re as full of shit as anyone else. Everyone wants the great job that pays bank–EVERYONE–but if you don’t have access to the people who are close to those positions–you don’t get them. So try not to rack up too much school debt.