Berkeley High cafeteria.

Berkeley High School once again made Newsweek magazine’s list of the top American public high schools, but for the first time in four years its rating went down rather than up.

BHS was ranked 446 out of 1,600 schools in the 2010 report. In 2009, the high school was ranked 271, up from the 2008 ranking of 286.

The slip is interesting. Newsweek calculates its scores by taking the number of Advanced Placement and International Baccalaureate tests taken at the school and dividing it by the number of seniors to come up with an index rate. In 2010, this rate was 2.401, a drop from last year’s 2.728. (Read a full explanation of its ranking system.)

But 2009 was the first year Berkeley High offered IB tests, so one would think that rate would improve. It is possible, however, that students who in past years would have taken an AP test switched to taking IB tests. Then there wouldn’t be a jump in the number of high level tests taken by students.

Newsweek states that the ranking on the list is not as critical as its index rate. As more schools in the U.S. find out about the list and submit their statistics, it is common for other schools to slip in the rankings, said the magazine.

Berkeley Unified School District spokesman Mark Coplan said BHS’ ranking slip may have had more to do with other schools improving rather than Berkeley High getting worse.

“It’s not based on a lessening of progress at Berkeley High, but an acceleration elsewhere,” said Coplan.

Newsweek’s rankings are controversial because they look at just one small aspect of a school. The author, Jay Mathews, believes strongly in the merit of AP and IB classes. He thinks they are the best indicators of performance in college.

‘To send a student off to college without having had an AP, IB, or Cambridge course and test is like insisting that a child learn to ride a bike without ever taking off the training wheels,’ writes Mathews.

In December 2009, U.S. News and World Report compiled its own list of the best high schools in the U.S., using completely different assessment tools. Berkeley High did not even make that list.

But once again Berkeley High seniors are going off to the nation’s best colleges.

Students this year were accepted at Harvard, Yale, Princeton, Stanford, Columbia, Brown, University of Pennsylvania, Williams, Dartmouth, Wesleyan, Vassar, Amherst, Sarah Lawrence, UC Berkeley, UCLA, UC Santa Barbara, UC Davis, UC San Diego, Michigan, U Mass, Kenyon, Pitzer, Pomona, Macalester, Bard, Whitman, Earlham, Kenyon, Oberlin, Grinnell, Skidmore, Berklee College of Music, the University of Edinburgh, St. Andrews, Aberdeen, and Durham. Students were also accepted at the California State Universities.

Other Bay Area high schools that made Newsweek’s list include Skyline in Oakland, Albany High, Acalanes, and George Washington, Mission, Gateway and Balboa in San Francisco.

Frances Dinkelspiel, Berkeleyside and CItyside co-founder, is a journalist and author. Her first book, Towers of Gold: How One Jewish Immigrant Named Isaias Hellman Created California, published in November...