Whether college is worth it or not depends entirely on what one is studying and why he/she wants to study that subject.
If you're someone who believes that knowledge and understanding of the world is more important to a happy life than money and success, then it's worth it. If you're pursuing a major in most maths/science fields, it's worth it if you're earning good grades and can get work/research experience at your university, and still often worth it if you're not and can't. If you're pursuing a major intending to attend a graduate/post-graduate program (law, medicine, etc.) and you're someone actually capable of achieving such a high level degree (meaning you're a nearly straight A student), then it's worth it.
It's certainly less clear in other scenarios, and I suppose whether college is worth it for most depends on whether our job market requires employees to have degrees or not. In my experience, a business that requires employees to have a college degree does so mostly because of a belief that the college educated have a higher quality floor than those with only a GED/high school diploma, not because performing the duties of that employee's job is impossible without a degree. Take a brief glance at our economy and you'll see plenty of successful salespeople/entrepreneurs who never graduated from college, but the perceived risk in hiring someone uneducated means that getting a job is likely much easier with a degree.