Standardized test scores at St. Charles North High School, St. Charles East High School and Sycamore High School jumped up from last year, pushing them up in the rankings among the top 100 high schools in Illinois, as calculated by the Chicago Sun-Times.

For a decade, the Sun-Times has based its exclusive rankings of schools on average scores on state achievement tests, not on the percentage who meet state standards -- a measure that's come under criticism.

Only 2009 reading and math results from the Illinois Standards Achievement Tests and the Prairie State Achievement Exams taken last March and April were analyzed. Results in those subjects can trigger sanctions under the federal No Child Left Behind law.

Results from St. Charles North students' tests placed the school 18th in Sun-Times rankings, up four notches from last year.

Kim Zupec, principal of North, said the reason behind the school's success is due mainly to a "well-grounded staff, which truly believes in and celebrates with their kids."

"We became better at teaching, and our kids became better at learning," she continued. "It's the student first here," whether that's through study halls centered on tutoring or the insertion of standardized test questions into the regular curriculum.

St. Charles East wasn't far behind its crosstown rival. Its state math and reading scores put it in 29th place in the newspaper rankings, 25 places higher than last year.

Robert Miller, the principal of East, said its accomplishment is simple: "We targeted the deficiencies from the previous school year."

On top of that, he said, East increased an already-high attendance rate, promoted more interaction among teachers, counselors and parents, and bumped up its graduation rate.

Sycamore was on the same wavelength.

Students there scored high enough on their exams to place Sycamore in 77th place -- 78 steps higher than last year and one of the biggest jumps among the state's top 100 high schools, according to the Sun-Times calculations.

Tim Carlson, the principal of Sycamore, said brutal honesty with faculty did the trick.

Last fall, administration laid "out the fact that we were underachieving to our faculty," he explained. "This was a great eye-opener for our faculty."

He said he hopes the school's achievement "is not an anomaly based on one class" and instead is the result of "structural changes," including aligning its curriculum districtwide and implementing more extensive reading programs in its grade schools.