I'll have to take your word for it, as the budget doesn't agree.
I can't seem to find an article that relates to CA but here's one from Chicago.
When the Chicago public schools lost a districtwide reading program and 90 percent of their funding for supplies last year, the situation went largely unnoticed outside the education community.
But when the city's high school principals threatened several weeks ago to eliminate extracurricular activities, including athletics, major corporations, radio talk-show hosts, and sports celebrities raised almost $1 million within weeks.
http://www.edweek.org/login.html?source=http%3A%2F%2Fwww.google.com%2Fsearch%3Fhl%3Den%26q%3Dwho%2Bfunds%2Bhigh%2Bschool%2Bsports&destination=http%3A%2F%2Fwww.edweek.org%2Few%2Farticles%2F1992%2F11%2F04%2F09sports.h12.html&levelId=2100&baddebt=false
Basically the state and local government give money to school distrticts and they spend it on everything involved with school including sports.