[1] Completed at a cost of $500,000 (equivalent to $8.8 million in 2023), ceremonies were held in October 1927 to dedicate the building "to the memory of Haddonfield residents killed in the World War.

[7] In 1992, Gwen Florio of the Philadelphia Inquirer described Haddonfield Memorial HS as "pretty, petite, and rich — the "trophy school" of South Jersey districts.

[28] The school was recognized as the Group II winner of the New Jersey State Interscholastic Athletic Association ShopRite Cup in 2005–06.

[40] The 1971 team won the inaugural Group II state title with a 2–0 win in the championship game against East Paterson (since renamed as Elmwood Park).

[41] The 1972 team finished the season with a record of 22–3 after defeating Glen Rock by a score of 3–0 in the Group II championship game.

[45] The team won the 2018 Group II title with a 43–39 win against Rumson-Fair Haven in the championship game played at RWJBarnabas Health Arena.

[47] The 1976 team defeated Pequannock in the championship game at Mercer County Park by a score of 2–0 to win the Group II state title and finish the season at 15–4–2.

[48] The 1977 team finished the season with a 15–1–3 record after winning the Group II title with a 1–0 victory against Montville in the tournament finals.

[49][50] A 1–1 tie in the 1978 playoff finals against Butler gave the team the Group II championship for the third year in a row, to finish the season at 17–0–4.

[51] The 1989 team finished the season with a 17–1–5 record after a scoreless tie with Belvidere after regulation and overtime in the Group I playoff finals.

[53] The girls swim team took the Public South B state sectional championship in 2003, topping Mainland Regional High School 87–83 in the tournament final.

[57] The boys cross country team has been led by Coach Nick Baker since 1982, and through the 2022 season he has compiled a 365-16 record, including 241 victories in a row, the last loss being in 1997.

[61] The 1987 team won the Group I title, defeating Highland Park High School in the semifinals by 5–0 and Verona by 4–1 in the finals.

[62] In 2007, the girls' tennis team won the South Jersey, Group II state sectional championship with a 4–1 win over Haddon Township High School in the tournament final.

[64] The boys' tennis team won the 2007 South, Group II state sectional championship with a 4–1 win over Sterling High School.

[66] The 1990 team fell behind early, but ended the Group I finals as co-champion after a 1–1 tie with Brearley to finish the season with a record of 18–1–3.

[75] The team won the 1999 Group I state title with a 61–45 win against Bloomfield Tech in the finals of the playoffs[76] and advanced to the Tournament of Champions as the fifth seed, falling to fourth-seed Ewing High School 59–55 in overtime in the first round and finishing the season with a 24–6 record, after Ewing scored a basket with less than a second left in regulation to tie the game.

[79] In 2007, the girls soccer team won the South, Group II state sectional championship with a 3–2 win over Woodstown High School in the tournament final.

[85] In 2017, the sixth-seeded football team finished the season with a 9–3 record and won the South Jersey Group II state sectional championship with a 21–17 win against top-seeded West Deptford High School in the tournament final.

[86][87] The 2018 team finished the season with a 13–0 record, winning the South Jersey Group II state sectional championship with a 23–12 win against Camden High School and defeating Hillside High School by a score of 17–7 in the Group II South / Central Bowl Game.