URBANA — For the fourth straight year, Uni High has been named one of Newsweek's "public elites" in the magazine's annual ranking of best American public high schools.

Only 16 schools earned the title of "public elite" in this year's list, released Monday, down from 17 last year, 19 in 2007, and 21 in 2006.

Public elites are those schools that did not make Newsweek's larger list of 1,500 top public high schools because, in the magazine's words, "their sky-high SAT and ACT scores indicate they have few or no average students."

The larger list of 1,500 schools was compiled according to a ratio created by education reporter Jay Mathews. Newsweek summarizes the ratio this way: "the number of Advanced Placement, International Baccalaureate and/or Cambridge tests taken by all students at a school in 2008 divided by the number of graduating seniors."

Mathews calls this the "Challenge Index."

The purpose of the index, according to Mathews, is "to honor schools that have done the best job in persuading average students to take college-level courses and tests. It does not work with schools that have no, or almost no, average students. The idea is to create a list that measures how good schools are in challenging all students and not just how high their students' test scores are."

As a result, this year's Challenge Index excludes all public schools that have an average SAT score of 1950 or above, or an average ACT score of 29 or above. Those schools whose SAT or ACT scores were too high were named public elites.

"Using average SAT or ACT scores is a change from the previous system we used, which excluded schools that admitted more than half of their students based on grades and test scores," Mathews writes. "That system penalized some inner-city magnet schools that had high Challenge Index ratings but whose average SAT or ACT scores were below those of some normal-enrollment suburban schools, so we switched to a system that we consider fairer and clearer."

Uni has been named a public elite every year since 2006.

Below are the 2009 public elites, with links to their official Web sites. Newsweek's comments about each school are included in quotation marks.

Newsweek's 2009 Public Elites

• Bergen County Academies
  Hackensack, N.J.
  "A collection of seven career-focused academies where students attend an extended school day."

• Bronx High School of Science
  New York City
  "One of the most famous schools in America for many years. It has a richly talented, ethnically diverse student body."

• Gatton Academy of Math and Science
  Bowling Green, Ky.
  "Juniors and seniors from all over the state are selected by scores, grades, and essays to live in their own Western Kentucky University residence hall, earning college credit as well as completing high school."

• High Technology High
  Lincroft, N.J.
  "The highest-scoring of the growing number of schools with this name across the country. This is a new species of high school, with a great emphasis on modern equipment and hands-on learning."

• Hunter College High School
  New York City
  "Another one of the city's greats, with a seventh- through 12th-grade program administered by Hunter College. It was an all-girls school until it went coed in 1972."

• Illinois Mathematics and Science Academy
  Aurora, Ill.
  "'Wayne's World,' the Mike Myers 'Saturday Night Live' sketch and film, is not the only cool thing associated with Aurora. IMSA is also a state-funded boarding school. It takes 10th through 12th graders and has a strong mentoring program."

• International Community School
  Kirkland, Wash.
  "Students are selected through a lottery to attend this school, which focuses on international awareness. It is one of the few public elite schools without a selective admissions systems. Instead, as happens sometimes, the lottery participants self-select into an academic powerhouse."

• Maggie Walker Governor's School for Government and International Studies
  Richmond, Va.
  "Unlike the science-math orientation of most of the public elites, the focus of this school is on world cultures and building students' leadership skills."

• North Carolina School of Science and Mathematics
  Durham, N.C.
  "This school, established in 1980 in an abandoned hospital, started the small but interesting trend of state-created boarding schools drawing bright and ambitious high-schoolers from all over the state."

• Oklahoma School of Science and Mathematics
  Oklahoma City
  "A state-funded boarding school that teaches all courses at the university level."

• South Carolina Governor's School for Science and Mathematics
  Hartsville, S.C.
  "Another state boarding school, this one is for 11th and 12th graders across the state."

• Stuyvesant High School
  New York City
  "Along with Bronx Science, probably the most famous on this list. It has been teaching the city's most academically ambitious students for several generations. It offers about 55 AP courses every semester, and has plenty of courses above that level."

• Thomas Jefferson High School for Science and Technology
  Alexandria, Va.
  "The most selective public high school in America, drawing mostly from the affluent households of northern Virginia and with one of the most talented faculties in the area."

• Union County Magnet High School
  Scotch Plains, N.J.
  "This selective-admission school also focuses on science, math, and technology."

• UNIVERSITY LABORATORY HIGH SCHOOL
  Urbana, Ill.
  "There is competitive admission for this day school on the campus of the University of Illinois. It makes good use of its higher-education environment."

• Whitney High School
  Cerritos, Calif.
  "Like Jefferson and High Tech High, a suburban version of the New York superschools, with very competitive admission, but unlike students at the state boarding schools, those at Whitney go home at night."