I'm afraid I disagree with GetItRight - especially for a kid who WANTS to go to college. While there's lots of talk of college not being for everyone (which I agree with), the fact remains that college graduates earn significantly more than high school graduates - $17,500 more for millennials today - even in the early years. Plus, a college degree is correlated with lower rates of unemployment and higher rates of marital stability. Google "college education income vs. high school" and you'll turn up studies from Pew and others.
But wait, you might say, this kid like computers, and in that field a degree may not make a big difference. Fair enough. But I don't hear ITT suggesting their son feels this is necessarily a lock, and I know a lot of unhappy 30 and 40-something computer folks who feel stuck in their current profession. College will let him test out what he loves, and possibly double major in a way that is valuable to him later. And if he learns it's not, even after graduation (a common occurrence for us all to change our minds as we learn and grow), any degree will give him a whole lot more career flexibility to change course and go in different directions.
That brings us 'round to the original question - how much to expect from the kid vis-a-vis contributing financially? I should say up front that I worked my way through college with a combination of scholarships, on-campus and off-campus jobs. I was a bank teller (all four years), did office work for a tax attorney (all four years), and was Residence Life for 2 years, which gave me half off room and board during my senior year. I also had a little bit in loan money ($15k coming out). I found working to be fun, interesting, and it meant I had my own spending money and independence, which was enormously satisfying. For many kids, being busier means you use your time better, so grades didn't suffer and maybe even benefitted.
It may be that you set an initial set of expectations for him: that he get the best job he can this summer and next summer, and maybe put a $ savings goal on it, half of which goes to tuition, and half of which is his initial college spending money - for everything (books, off-campus food, clothing, etc.). I don't know what jobs are available in your area for him, or how much in-state tuition might be, but I think you want to line these up to make the goals realistic so that he can succeed (but needs to work hard to do it). You don't want to set an impossible goal that leaves him feeling discouraged instead - but this may depend on his personality and what motivates him.
We have saved to cover college for our 3 kids, but don't plan to cover all of it for all the reasons you describe - they'll value the education (and working is itself an education) and the perspective you get working tough jobs like busboy (my least favorite of my high school jobs) is important in terms of how you treat people later I think......
Just my 2 cents.