[7] The high school's current Tudor Gothic-style building, constructed at a cost of $500,000 (equivalent to $8.9 million in 2023) opened in September 1924.

In 2012, the board of the Merchantville School District decided to send its students to Haddon Heights High.

[12] The plan was approved by the Commissioner of the New Jersey Department of Education, and students from Merchantville began attending the school in September 2015.

[14][15] Scott Strong, the chief administrator of the Merchantville district, stated that "Haddon Heights offers the right programs, the right diversity and really met our needs.

[37] At the USSBA Yamaha Cup competition in October 2012, the marching band came in first in the 1 Open group, winning awards for Best Visual and Best Guard.