Your characterization of adjuncts is unnecessarily harsh. Many simply enjoy teaching in a university environment and aren't "desperately clinging" to anything.
Anyone who describes themself as an adjunct professor as if it’s sonetbing other than a hobby should be encouraged to get a job that isn’t shit. Teaching high school is vastly less intellectually rewarding but the holidays are better and so is the insurance and the pension.
I looked into this in my state. Getting your foot in the door as a teacher in a public school would require someone with a PhD in say, mathematics, physics or computer science, to go back to grad school for a masters in education. Not sure that's an option, and is also ridiculous considering I just spent six years in grad school. You could do TFA as a backdoor, in many states, but that is probably an even worse deal for you physically and emotionally than being an adjunct.
But you need to get your resume in front of the right people -- namely, folks in the central office (or maybe principals) who view your area as a strategic/difficult hiring area. Easy peasy in CS these days...
Also check out private schools.
My understanding is that private (k-12) schools pay dramatically less than (unionized) public schools. I've had family and friends who taught even at very expensive secular private schools, who then moved over to public school because the pay, pension and benefits were dramatically better.
I don't have hard numbers, but my impression from talking with family and friends is that you are much better off as an adjunct at a public college than as a k-12 teacher at even a prestigious private school or non-union charter school, though a union teaching job at a public k-12 school pays better and is much more stable than both.