Another awesome idea!! I really feel as if this is a great solution for those who maybe want to go straight into a profession and just need a year of extensive training. It saves money and opens doors for them. As far as an experiment to test the idea, I think conducting a survey of senior/junior high school students and college students would be effective. Then we could see how the idea is received by both kids who are looking at college options currently, and from a retrospective point of view. Another target group to reach out to would be servers, bartenders, and blue collar workers to see if this option would have changed their career path in many ways. When I was waitressing a lot of my coworkers were people who did go to college or had gone but had to drop out because they didn't have enough money. If they had been able to finish in the two years of college they could afford, their future might have turned out a lot differently. I could see this turning non-consumers of higher education into consumers.
I love this idea. It reminds me of a program that Texas did called the Texas Tomorrow Fund. Essentially when I was a baby, my parents locked in the tuition prices of a public college education for me in my future. Now all of my tuition costs are paid for by this program and provided a lot of financial relief for my parents and I now. You asked for possible enrollment type data, since I feel this program is kind of similar, I found a 2013 report with a lot of data that is hopefully useful for you. http://www.tgtp.org/docs/TGTPAnnualReport2013.pdf
Here's the general website with information on the program: http://www.texastomorrowfunds.org/
I really like this idea. One of my best friends in college struggled all through high school and struggled to get into college. She put through these societal pressures making her feel like it was the right path. She realized that what she really wanted to do was cosmetology school, and now she excels at it. Another one of my good friends went to trade school to be a car mechanic. There are so many options besides college and I think financial aid to those options are important as well. Just another thing to consider.