NEW YORK — Darci Hemleb Thompson had been on the lookout for Alice D’Addario for many years. From her home in Hampton, Va., Thompson, 49, who is married and has a 12-year-old daughter, was determined to find D’Addario on the Internet. She tried every search engine and networking site she could find.

About 18 months ago, she hit the jackpot.

“Nice to see one of the greatest teachers of all time on Facebook!” Thompson wrote on D’Addario’s wall. “I love to go to your page just to see your smiling face. Even your eyes still smile. You are an amazing person!”

D’Addario was Thompson’s Advanced Placement history teacher at Walt Whitman High School in Huntington Station, on Long Island, in 1977.

“She had such a huge impact on my life as a young adult,” Thompson said, describing her tumultuous teenage years living with two alcoholic parents and experiencing early symptoms of multiple sclerosis.

“I was depressed and so sad and so isolated, and she reached out and saved me,” Thompson added. “Facebook gave me the chance to tell her, ‘You’re the one who pulled me through.’ ”

At a time when public school teachers are being blamed for everything from poor test scores to budget crises, Facebook is one place where they are receiving adulation, albeit delayed.

The site has drawn more attention as a platform for adolescent meanness and bullying, and as a vehicle for high school and college students to ruthlessly dissect their teachers. But people who are 20, 30 or 40 years beyond graduation are using Facebook to re-establish relationships with teachers and express gratitude and overdue respect.

Brad Scharff, 49, a finance manager at Time Inc. who knew D’Addario through her role as the junior class adviser, also reconnected with her online.

“It was like bringing back a lot of the more positive aspects of the high school years when I saw her on Facebook,” Scharff said.

Tribute pages

Over the years, teacher tributes have come in broad formats, in movies like “To Sir, With Love” and “Stand and Deliver” and in TV series like “Room 222.” Now, on Facebook, the praise is personalized, more widespread and more democratic.

On Facebook walls and dedicated tribute pages, the writings betray emotions that students dared not display in their youth. They include moving messages (“You inspired each of us to learn and go beyond what we thought we could achieve”), lighthearted claims on old debts (“You owe us a pool party — you promised us one if the Dow ever reached 3,000”) and recollections of specific events (“You got me out of detention one time”).

In the weeks before the death last month of Jerry Sheik, a retired band teacher from Intermediate School 70 in Chelsea, N.Y., his wife, Judith Kalina, said he was overwhelmed by the praise written on a Facebook page created in his honor, “Sheik’s Freaks Reunite: A Celebration for Jerry Sheik.”

The page has 135 members, mostly students from the 1970s who played in the stage band Sheik conducted. They have posted old band photos and recalled their rendition of “Oye Como Va.”

One former student, Melissa Sgroi, wrote, “There are few people that you look back on in your life and know they left an indelible mark. Thank you Jerry Sheik for being one of those people.”

Another of Sheik’s students, Ned Otter, said, “Jerry was the first one to put a sax in my hand.” Otter went on to play saxophone professionally, touring with Dizzy Gillespie. He is one of nine overseers of the Sheik’s Freaks page.

“He played a critical role in my life,” Otter added.

The tributes underscore what researchers have identified as a major force in adolescents’ lives, said Jacqueline Ancess, a researcher at Teachers College at Columbia University. “The most powerful factor in transforming students is a relationship with a caring teacher who a kid feels particularly connected to,” said Ancess, who added that many students had told her that if not for a particular teacher, they would not have graduated or would not have taken a certain direction.

Reconnecting

Some former students have tried to recreate old roles, using Facebook messages to draw a teacher who had nurtured them back into their lives.

Lisa Nielsen, 41, a former library media specialist at Public School 175/Intermediate School 275 in Harlem, which she said was for troubled students, logged on to Facebook one day last year and saw this message:

“Hey Ms. Nielsen, I had to find you because you made a wonderful impact on my life. If people only knew how great of a teacher you are.” The message continued, “I know it’s been at least 10 years since you took me under your wing,” and added, “Let’s talk, got a lot to say!”

The writer, Keryce Davis, who was a sixth-grade student of Nielsen’s, is now 22 and works as an optician in Washington, after receiving an associate’s degree. Nielsen is glad to re-enter Davis’ life, and said they were discussing possibilities for Davis’ future.