Khan Academy allows me, with no overhead whatsoever, to pick (or refresh a skill), whenever I want. If my math skills aren't up to snuff for a hobby project I'm working on, Khan Academy is there. If I can't remember how a transistor works ... Khan Academy has me covered.
Compare this with the incredibly high overhead of high school and 4 year degree programs. If I just want to take a refresher engineering class at the local University or Community College, I have to go through the full admissions process, provide a full academic history, justify my reason for being there, and then work at a preset pace and on someone else's schedule. If I'm stuck at the undergraduate level, I have to take a slew of general ed courses totally unrelated to what I actually want to do.
Contrast this with frictionless learn on-demand education.
There are, obviously, downsides:
- Not all topics are covered.
- The depth of coverage is not on par with a university education.
- No access to very expensive university equipment
- No one-on-one access to a professor
- No student discounts on expensive software
Despite those downsides, the format has worked great for me.
In my ideal world, formal K-12 and college education would be comprised of:
1) Elective projects that rely on a broad swath of skills.
2) Courses to be taken in concert with the projects to provide requisite skills, as those skills become necessary.
I agree with your general sentiment but I feel like your premise oversimplifies the situation.
I didn't have to apply, it was really trivial. I took one course, and they were happy to let me do so.
The opposite is true for "hard" sciences like chemistry, engineering or CS, where expensive laboratory equipment is necessary and where teaching resources are scarce (due to higher private-sector demand). There, courses are expensive, demanding and small in number, so they are usually inaccessible to the layman.
The course offerings are generally constrained, and the courses themselves are often lightweight versions of the university course -- assuming that the subject you want is covered at all. The facilities for continuing education courses are also often less robust.
Take CCA in San Francisco. This is a highly considered arts college, and they offer a small number of introductory extension classes:
Compare to their full course offering:
You'll have to drill down on individual categories to explore the full breadth and depth.
Continuing Education offerings are rarely a substitute for the quality of courses they offer to a matriculating student.
Given how often educational institutions have raised their tuition in recent years, I'd love to see them institute a program where they charge a (possibly large) fee to allow non-matriculating adults to audit a course, without limitation or requirement, and use those fees to subsidize enrolled student tuition.
However, this may be a shift too far in the "trade school" direction for their comfort.