During the 97^th year of Harris Memorial College, in the year 2000, the High School Department began operating following the standard curriculum of the Department of Education. In 2003,when Harris celebrated its Centennial Year, the construction of the high school building was completed and was also granted government recognition by the DepEd. In 2004, the first batch of students graduated and a number of them were admitted to prestigious universities such as the University of the Philippines, Miriam College, University of Sto. Tomas, and Ateneo.