What makes you think that?
Without having to pay for the net subsidy to other states, it could lower its taxes if it wanted.
It's not bottom of the barrel for education. Mississippi, for example, is much worse. On the 8th grade NAEP, the percent of Californian students that ranked proficient or better was 27, 28, and 24, for math, reading, and science, respectively. For Mississippi, it was 22, 20, and 20. Alabama was also worse than California across the board (17, 26, 21). Louisiana, too (18, 23, 22). And there were others that were worse overall even if they weren't worse across the board (e.g., WV). Granted, California is no Massachusetts (51, 46, 44), but for a state that has the additional challenge of teaching so many people for whom English isn't a first language, it's doing OK.
If it took that money that's been earmarked to support the leech states, and instead used it to pay down debt, how long until it would pay it off?
Why?
It already polices those cities. Why would resource requirements change? Granted, they wouldn't have help from the federal government -- but, again, it's a net-contributor state. If that money stayed home instead of going to DC, there'd be fewer economies of scale, to be sure, but would that be enough to offset the gain of having the net amount stay home?