General welfare clause upheld time and again by the SCOTUS.
It doesn't take a rocket scientist to know that you're odds are very slim if you do not have a college level education and for most people that means a college degree. Promoting the general welfare is tantamount in many cases if not most, to promoting the education of the citizenry.
Additionally, more persons educated to a college level will undoubtedly benefit the nation.
Education is different from advanced education. Now if Bernie wants to try and take free college to the Supreme Court, I would anxiously await that day.
College is a personal investment, not a social investment. If you graduate college and take the right courses, you will make much more money than those that don't. The federal government should not be in charge of making personal investments and no, not covered in the general welfare either.
A house is an investment, but the government doesn't give you money for a house unless you are a veteran and it's included in your benefits. The stock market is an investment, but the government doesn't give you money to play the market. Real estate is an investment, but government doesn't give you money to flip houses.
In our US Constitution, you will find phrases like "promote the general welfare" and "provide the general welfare" but nowhere in our Constitution does it say fund the general welfare.