Though most ex-students were over 65 years old, they kept in touch easily in the era of social media and email.
Mr Haycock helped write and publish a yearbook of sorts last year, detailing where former students were and what they had been up to since leaving school.
The reunions had been taking place for at least 15 years annually, with a "grand reunion" every five years.
"The people just keep asking for them. We talk about the old times, romances, feuds ..."
It was a different time when the students were at college between 1946 and 1957.
At the reunion former students would indulge in a bit of nostalgia: the school theatre put on a play with actors wearing black face, holding hands at school was risqué and Tauranga was just a small town.
"Everyone knew everyone," Mr Haycock said.
It was just "astonishing" what pupils had gone on to do with their lives.
The reunion will be on May 21 at the Tauranga Citizens' Club.
This year ex-pupils of Tauranga College and high school sweethearts Gary and Marlene Ware would be the speakers at the luncheon.
There would be more speeches, live music and a display of old photos from school days.
Tauranga College:
-1946-1957 Tauranga District High School became Tauranga College in 1945 when it moved to a new location between 15th and 16th Aves.
- Arthur Nicholson was the first principal.
- In 1958 the co-ed school was dissolved to create two single-sex schools.
- Rows of 41 totara trees planted along 15th Ave planted to commemorate 41 ex-pupils of Tauranga College who died in World War II.