Six public high schools in Connecticut made big enough gains in reading and mathematics test scores this year to be removed from an annual academic warning list under a federal school improvement law, state officials announced Thursday.

The six contributed to an overall increase in the number of high schools in Connecticut meeting the standards of the federal No Child Left Behind Act.

"We're pleased with the results, that's for sure," said Russell Duffy, an assistant principal at H.C. Wilcox Technical High School in Meriden, where scores improved after officials revamped curriculum, provided more training for teachers and added extra labs in reading and math.

Wilcox was removed from the warning list after making sufficient progress this year. In all, nearly 80 percent of the state's 179 public high schools met the federal standards.

Still, 40 high schools failed to have enough students reach the proficiency level on the Connecticut Academic Performance Test, a spring test of high school sophomores. Last year, 48 schools were cited.

The latest list includes four schools that have failed to meet standards for the past five years: Weaver High School in Hartford, Bassick and Harding high schools in Bridgeport and J.M. Wright Technical High School in Stamford. Because Weaver and Wright receive federal Title I funds, they now face major reorganization under the federal law.

At Weaver, for example, officials have already begun assigning students to smaller "schools within schools," said interim Hartford Superintendent of Schools Jacqueline Jacoby. The district also has hired a consultant to develop further recommendations, possibly including steps such as a longer school day and school year, she said.

No Child Left Behind, the centerpiece of President Bush's school reform agenda, calls for a shake-up of schools that don't make adequate progress and is designed to identify academic problems among specific groups of students. A school or district can be cited if even one group of students - such as members of a minority group, special education students or non-English-speaking children - fails to meet standards.

Although some schools were cited because too many special education students or members of other groups missed the proficiency standard, 25 high schools were identified because too many students overall were performing poorly in math, reading or both subjects.

"This cannot continue," said interim state Education Commissioner George A. Coleman. The results, he said, lend urgency to a state effort to reform secondary education. A reform plan is expected to be ready for review by state officials this school year.

Coleman praised the six schools that climbed off the warning list, saying they are models that other struggling schools can follow. Once a school has been cited, it can escape the list only by making sufficient progress two years in a row. In addition to Wilcox, the schools included Ansonia High School, Bristol Central High School, Derby High School, Rockville High School in Vernon and Bullard-Havens Technical High School in Bridgeport.

"We need to create the capacity to learn from these schools," Coleman said. Wilcox and Bullard-Havens are part of a statewide technical high school system that has had encouraging gains in scores on the 10th grade test, an upswing credited in part to an aggressive reform movement that began two years ago with the arrival of Superintendent Abigail L. Hughes. The reforms included scheduling changes, teacher training and an extensive revision of curriculum.

At Bristol Central, educators have shifted over the past three years to a style of teaching that adjusts instruction based on how well students are grasping a set of predetermined skills, Bristol Superintendent Michael Wasta said. The gains in test scores indicate the program is working, he said.

At Rockville High School, teachers are in the second year of working in "data teams" that track students' scores on standardized tests and class work, said Principal Brian Levesque. "They figure out where their kids are falling short and they try to build up those skills."

Although the warning list was slightly smaller this year, educators predict it will grow dramatically over the next several years as standards for No Child Left Behind grow tougher. By 2014, the law will require 100 percent of students to score at proficient levels in reading and math on state tests. This year, the standard was set at 69 percent in mathematics and 72 percent in reading.

Courant staff writers David Owens and Loretta Waldman contributed to this report.