What Happens After High School?

I am trying to stay away from policy talk, but I have long been interested in studying the real effect of a high school education on students.  There is remarkably paltry data on this subject, and I'd appreciate any leads here.  I have recently come across two reports.

Here, Anne Hyslop of Education Sector lays out the problem, and its impact on teachers:

Data That Matters: Giving High Schools Useful Feedback On Grads' Outcomes

And here is the most in-depth report I've found on the subject and its impact nationally:

Promoting Economic Mobility By Increasing Post-Secondary Education

My one idea on this subject is that high schools need to be working much more closely with colleges, rather than "passing the buck" in both directions.  Perhaps more on this later.