For the first time, most of California's public schools have met or exceeded the goal the state set for academic achievement on a closely watched index, results of which were released today.

About 53 percent of the state's schools scored at or above the target of 800 on the Academic Performance Index, compared with about a quarter -- or 68 -- of Kern County's 265 schools.

The index ranges from a low of 200 to a high of 1,000. The API is a composite score that combines information across grade levels and subjects. Any school scoring 799 or below fails to meet the state's identified performance goal.

The Fruitvale School District in northwest Bakersfield led Kern County with an index score of 864.

"We're obviously ecstatic about the results," said Assistant Superintendent Matt Torres, who attributed the district's success to a culture of cooperation between administrators, parents, students and teachers. "We're proud of our teachers, especially, for their willingness to share techniques for what works in the classroom, and being open to hearing suggestions and willing to experiment."

The K-8 Buttonwillow Union School District, with a score of 662, was the lowest of the major local districts excluding the Kern County Office of Education, which has a large number of special-education students and youth involved in the Kern County Juvenile Court system.

Buttonwillow Superintendent J. Stuart Packard, who only recently joined the district, noted that 68 percent of his students are English learners, but there still was 0.9 percent improvement over 2011.

"We increased in all of our subgroups, including English learners. All of them rose," he said.

Packard added that the district hired four new teachers this year, and has initiated new training programs.

"We're just now getting a chance to implement our changes," he said.

State Superintendent Tom Torlakson was excited to see more than half of the state's schools achieving their goal, noting that 10 years ago only 20 percent of California schools were able to do so.

The state's schools still mostly fell short of the minimum standard established in the federal government's No Child Left Behind program, however. California and more than half of the nation's other states are in the process of pursuing waivers from key provisions of that mandate from the U.S. Department of Education.

Among other things, the bill President George W. Bush signed into law in 2002 established deadlines for making students proficient in state testing, and strengthened qualifications required to teach core subjects.

Kern County schools have been inching toward the state's benchmark little by little for about five years now, said Desiree Von Flue, division administrator for the Kern County Superintendent of Schools office.

"We're seeing consistent and steady growth toward that 800 target," she said.

Five years ago, only 33 schools scored an 800 or higher, compared with 56 last year and 68 this year.

Results were less dramatic in the greater Bakersfield area.

Districts in the greater Bakersfield area were largely flat year-over-year. Scores for the Bakersfield City School District (731), Fruitvale School District( 864), Greenfield Union School District (774), Rosedale Union School District (836) and Kern High School District (730) all rose very slightly.

Panama-Buena Vista Union School District dipped less than 1 percent to 797, costing it last year's spot above the coveted 800 mark.

It's normal for index scores to jump around a little bit from year to year, said David Onsum, the district's research and evaluation services director. Even in good years, he said, the district tweaks things here and there with an eye toward improvement. This year, obviously, that scrutiny will be more intense.

"These numbers are not particularly helpful to really identify what the factors are that are contributing to improvement or lack of growth," he said. "It's like taking your temperature. You know you have a fever, but that doesn't tell you what organ systems may be compromised or what virus or bacteria may be a problem. It's like a red flag. It tells us to look a little deeper to try to figure out what's going on."

The challenge is particularly daunting in light of a state budget crisis that has seen payments to local districts slashed for several years running, Von Flue said. Still more cuts are looming if voters fail to pass one of two statewide measures on the November ballot designed to stop the bleeding.

That's why a lot of districts are establishing "professional learning communities," setting aside regular time for teachers to share best practices, attend training sessions and learn how to take advantage of new technologies that zero in on student weaknesses and offer strategies for addressing them.

"Most of the time that doesn't cost the district any money," said Kern High School District spokesman John Teves, who credited such meetings with his district's improvement. "It just requires people to sit down and communicate."