So when your students ask why they need a college degree, point them towards this article: Calculating the Value of a College Degree. As noted:
We always knew that people with an associate degree earned less than those with a B.A., on average. That is still true. The difference is about $500,000 to $600,000 throughout a career. Over the course of a lifetime, a college degree is worth an extra $1 million in earnings ... (over a high school diploma).