what exactly do you learn in college level english?

I am considering going back to college for English or writing of something to do with words. But, I am not too excited about the notion of being a broke college student again. I want to improve my ability to write but if all I am going to do is read, write, and interpret is it worth my time? Am I better off studying at home and do freelance work in my sparetime and go from there?

I am curious because I see some jobs asking for English majors but I'm wondering what do they learn in college that was too tough for them to understand in high school.

If u could list some specific things done in college English i would appreciate it. I know they have you read, do critical thinking and interpreting , grammar, vocabulary, and form. I may just be ignorant but 4 years seems like allot of time to learn to spell right.

Thanks everyone.