San Francisco reduced the number of schools considered the worst of the worst in the state, according to rankings released Thursday.
California's schools are ranked annually according to the state's Academic Performance Index, which is a composite of test scores from the previous spring. Thursday's rankings reflect students' performance from spring 2011 and give parents and real estate agents a simple way to compare schools and districts across the state.
Seventy-three percent of schools in the San Francisco Unified School District maintained or improved their rankings, according to a statement from the district. Overall, 43 percent of district schools are ranked in the top 40 percent in the state, matched by another 43 percent of schools that rank in the bottom 40 percent.
The schools are ranked in two ways on a scale from 1 to 10, with 10 the highest. The first method ranks a school's test scores with all other schools in the state and the second compares schools that share similar demographic characteristics, including socioeconomic status, class size and percentage of students who are English learners.
Nine schools were ranked 1 in both categories this year, down from 14 in last year's rankings.
District spokeswoman Gentle Blythe said one possible factor behind the better rankings was that in 2010-11, the district required all schools to regularly assess how students were understanding their lessons.
Assessments were made three times a year for elementary schools and twice a year for middle and high schools.
"It looks like on the plus side we've reduced significantly the number of schools that are 1-1," Blythe said. "That's something we've focused on and I think that's promising in terms of moving in the right direction."
Schools no longer with the worst ranking were Bret Harte, Bryant, Junipero Serra, Paul Revere, Rosa Parks, and Sanchez elementary schools; Everett Middle School; and June Jordan School for Equity.
Junipero Serra made the biggest move of the group, scoring a 2 statewide and a 3 against similar schools.
Cesar Chavez Elementary School, a school that received 1 in both categories last year, was not ranked this year because an "irregularity in testing procedure occurred during the Spring 2011 testing," the Department of Education's website stated.
Once again, four San Francisco schools earned the highest possible ranking of 10 in both categories, including John Yehall Chin, Sherman, and Ulloa elementary schools; and Lowell High School.
The news wasn't all good. Dr. Charles Drew College Preparatory Academy, El Dorado Elementary School and Metropolitan Arts & Technology High School slid to a 1 rating in each category.
In the Oakland Unified School District, 24 schools had 1 in each category, compared with 22 last year. But seven schools had the highest rating, compared with four in the last report.
Blythe noted that as useful as the rankings are, they might not be telling the whole story.
"Schools can make great gains and still have the same rank because it's how well they are performing in relation to other schools," she said.
To view the school rankings, go to links.sfgate.com/ZLLB.