As Gene Horrigan prepares to leave Shepaug Valley High School, it is with a wealth of emotion in saying good-bye to a faculty and student body who have been the focus of his professional life for 21 years.

"The dynamics of a high school environment are such that there is a tremendous interaction with people and ideas," said Mr. Horrigan, the school's principal. "The interaction is so exciting and the generation of ideas that comes from that interaction is so intense -- from that perspective, my Shepaug experience will be hard to replace."

Mr. Horrigan, who is leaving Aug. 26, will leave a legacy of change and growth that has led Shepaug to be known as one of the premier public high schools in the state. In 1998, the school was honored as a Blue Ribbon School by then governor John Rowland.

The senior project, developed under Mr. Horrigan's initiative, is being studied by NEASC for inclusion in its requirements for accreditation of high schools. It is also emulated by many high schools across the state, said veteran English instructor Douglas Winkel.

"He's been a great leader, helping to shape education and introducing new ideas and new programs," said Mr. Winkel, who directs the theater productions at the school. "He was a mentor in encouraging me to try new teaching techniques and getting the best from my students."

Mr. Horrigan is modest in discussing his leadership at Shepaug.

"I didn't bring a vision here," he said. "Together we developed a vision over the early years, one based on the question of, what do we want to assure each student is able to do in the world after he or she walks through the graduation ceremony?"

While Mr. Horrigan may not take direct credit for the vision, he did bring in leading intellectual thinkers on education in those early years. Ted Sizer, the head of Brown's Education Department at the time, came to the school. Douglas Heath, who had done a leading study on what it takes to be an effective adult and how to best develop those qualities in students, was also asked for consultation.

"What drives the education at Shepaug is high academic expectations and helping each student achieve competency in important life skills," said Matt Perachi, the school's athletic director. "Gene was the driving force that brought that about."

Mr. Horrigan came to Shepaug from Irondequoit High School in Rochester, NY, where he was the principal overseeing a faculty of 140 teachers and five assistant principals.

"I knew, after that, large schools have a culture and momentum that makes it very difficult to ask the big questions of education, and to then get people to answer those questions and then implement them," he said.

"Shepaug was a small school with a reputation of being a good school," Mr. Horrigan said. "I thought, maybe I could deal with those big questions of education in a thoughtful and deliberate way here. I have been able to do that."

Shepaug Valley High School's faculty members credit Mr. Horrigan with bringing a fuller arts program to the school. They praise him for understanding the value of athletics in the makeup of a high school education and say he attended many sporting events.

He took the senior class on its first out-of-state trip and has gone on every senior class trip since. He supported outdoor graduation ceremonies on the school campus. And he initiated the students' World Affairs Forum.

Mr. Horrigan also introduced block scheduling, which created 84-minute class lengths for delving fully into learning activities in which the students can analyze, research and develop a defensible solution to problems.

"I have tremendous respect for Gene," said Irene Allan, who sat on the Region 12 Board of Education for 12 years, three of those as chairman. "Gene Horrigan is regarded as one of the finest principals in the state. He deeply cares about the students at Shepaug and is supportive of his staff."

"He works toward making Shepaug the best it can be," she added. "There's nothing wrong with change, but he will be a tough act to follow."

A graduate of Joel Barlow High Schol in Redding, Mr. Horrigan said his retirement plans are to spend time with his five adult children and their families, including a grandchild on the way.

He and his wife plan to travel, write and "continue learning," with a commitment to furthering answers to social issues, most immediately, health care.