Let's assume, for sake of argument or column-writing, that the fundamental task of any public school system is to maximize the number of students who graduate from high school and are ready to either enter the workforce or further their educations.

Thanks to a new report from the U.S. Department of Education, which for the first time provides state-by-state comparisons of graduation rates on common criteria, we now know where California ranks – and it isn't very high.

Just 76 percent of our high schoolers graduate, putting us 32nd in the nation, roughly on a par with most Southern states. Iowa is the highest at 88 percent, and the District of Columbia is lowest at 59 percent.

Drilling into the data provides very strong clues as to why California fares so poorly.

Our Asian and Pacific Islander students are on a par with students in Iowa at 89 percent, followed by white students at 85 percent, but Latinos have only a 70 percent graduation rate and black students just 63 percent.

Dig a little deeper and another aspect of the situation emerges. California teens with "limited English proficiency" have just a 51 percent graduation rate.

California has the nation's most ethnically diverse population. Nearly 60 percent of its 6 million K-12 students are either Latino (51-plus percent) or black (7 percent), and about 13 percent of those in high school are "English learners."

Local school systems with large percentages of Latino and black students and/or those with limited English proficiency have below-par graduation outcomes. Los Angeles Unified has more than 10 percent of the state's public school students, its students are more than 80 percent Latino and black, and its graduation rate barely tops 60 percent.

Is the answer more money?

California spends $62 billion a year on schools, or just over $10,000 per student. That's somewhat below the national average, although not as low as often depicted, and very close to what much-smaller North Dakota spends. But its graduation rate is 86 percent, 10 points higher than California's.

North Dakota, of course, is also the polar opposite of California in demographic terms with an overwhelmingly white, English-speaking population. And its white, Asian and Pacific Island students have graduation rates very similar to their California counterparts.

So education may need more money, but it should be concentrated on helping Latino, black and English learner students, whether in public schools or charter school alternatives.

Gov. Jerry Brown wants a "weighted formula" that would direct much of the new money being generated by Proposition 30 toward students with the most learning deficiencies, but there will be great resistance to such change.

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