DES PLAINES, Ill. -- The entire student body of Thomas Jefferson Charter School would barely fill two lunch tables at a typical Illinois elementary school.
With only 68 students enrolled, the suburban K-8 school can boast of the individual attention its students receive. Principal Char Berry also is proud of the school's diversity -- last year, about half of the students came from non-English-speaking homes.
But those assets became liabilities the first time the school reported scores on the state's standardized tests. The tiny enrollment meant any one student could skew the school's scores. And less-than-stellar raw numbers in reading and writing didn't speak of students who came to school not knowing a word of English.
An analysis of standardized test data the State Board of Education recently released for the 2000-2001 school year found mixed results for charter schools. Some schools outperformed their districts, while others scored below the district average. Some went out of their way to enroll low-income students, while others attracted fewer poor children than their districts as a whole.
Five years after Illinois opened its first charter school, the scores show how difficult it is to measure an experimental school by just one standard.
"It's very important to understand the school behind the scores," said Greg Richmond, director of the Charter Schools Office for Chicago Public Schools. "Every school tends to have a puzzle that you can start to put together based on a variety of data."
The Legislature created charter schools in 1996 as a way to bring private school benefits into a public school system. The schools are run by private boards and operate largely free from state rules, creating their own curricula within the guidelines of a "charter" granted by the district, typically for three to five years.
After that time, districts can opt to shut down a charter school if school board officials determine it hasn't made progress.
Chicago reached its cap of 15 charter schools this year. Three others are in Chicago's suburbs and five are downstate.
Most of the schools have a theme, such as Hispanic culture, world studies or the arts. Thomas Jefferson opened in 1999 and follows the Core Knowledge program, which stresses basic skills.
In 2000, the first time Thomas Jefferson reported scores on the Illinois Standards Achievement Test, students passed less than half of all the tests they were given. Last year, that number climbed to about two-thirds of all tests.
The school's overall passing percentage was below its students' home district, Community Consolidated 59, although Thomas Jefferson students did outperform the district in some subjects.
"Whether District 59 is doing better than we are is not a fair question," Berry said. "We are offering something different. It's a choice people didn't have before."
The number of parents making the charter choice may be a better measure of a school's performance than any one test, said Robert Hill, superintendent of Springfield District 186.
Parents in Springfield expect waiting lists to enroll students in the Ball Charter School, which opened in 1998. The school has an extended instructional year and emphasizes math and foreign languages.
Springfield Ball has consistently outperformed the district on the ISAT tests. But Hill noted that the school has a much lower percentage of poor children than the district as a whole -- 23.4 percent compared with 50.1 percent -- and performs on par with other schools in the district with similar demographics.
Even so, Hill said the district, which does not oversee the school, has been able to learn from its success.
"We see the charter school as a laboratory for good ideas," Hill said.
Richmond said Chicago also has been impressed by the majority of its charter schools, even though many have performed poorly on the state's tests.
Of the seven Chicago charter schools that took the ISAT tests last year, three did better than the district. But in only one Chicago charter school -- North Kenwood/Oakland -- did students pass more than half the tests they were given.
Richmond said most of the schools are in the city's poorest neighborhoods. And some seek dropouts or those at risk of failing.
Chicago looks at other measures, such as gains on the Iowa Tests of Basic Skills, to determine how a school is doing. Six charters are up for renewal by the end of the year, and Richmond said some may not be renewed.