The first session opened in Morgen's hall, a one-room wooden structure, at Morrill's Corner, in the fall of 1874 with 31 students attending.

In 1878, Deering moved to the old wooden Longfellow School which was located opposite from Central Square Baptist Church.

By 1897, with Mr. E. H. Crosby as principal, the school had grown so plans were made for a new building which was to have fourteen recitation rooms, a library and a large assembly hall.

Just before the building was to be occupied, Mr. Crosby, Principal, was killed by a train at "Woodfords Crossing" during a rain storm.

Yet only fourteen years after 1898, the school has grown so that an addition, the Annex of Lincoln Junior High was built.

In 1922, the main building was constructed and housed 826 students, and in 1932 a small wing was added to complete the structure.

Sophomores, juniors, and seniors occupied the Stevens Avenue School in which many improvements had been made during the summer.

During the 1978 school year, a DHS Building Committee with architectural firm Wadsworth, Boston, Dimick, Mercer & Weatherill began designing the new addition.

Construction of the new addition began in the summer of 1981 when David Wallace became the new principal of Deering High School.

Under his leadership the provisions of Maine's Educational Reform Act were implemented, and ten years NEASC re-accreditation was awarded.

[6] In October 2013, Deering High School announced it would offer an Arabic language course as part of their new international curriculum.

[7][8] Memorial Stadium is located on Ludlow Street near Deering High School, it is an artificial turf surface and is the home field for DHS outdoor sports teams.

The Deering Rams won the Maine Class A Boys' State Basketball Championship on March 3, 2012.