Manggahan High School, formerly Rizal High School Manggahan Annex dawned thtough the courageous heart of Mayor Vicente P. Eusebio. While seated as city mayor of Pasig City, he deemed it wise to open a school at Barangay Manggahan so that the children of the bangay and other neighboring barangays can avail of secondary education.

        The school is located at Magsaysay Avenue, Karangalan Village, Manggahan, Pasig City at the site of former ANRRENN, a rehabilitation center for drug addicts, it was reported then, That ANRRENN was operating illegally and NHA department owned the lot. Because of this reasons and complaints, the people of Pasig headed by Mayor Enteng Eusebio, in full force worked as the one to get and win the fight. It was in 1999, RHS Annex Manggahan started to operate with Mrs. Nancy Tolentino as Head Teacher =in=charge.

        The first building was constructed sometime in 1998 during the administration of Mayor Vicente P. Eusebio and inaugurated on May 30, 1999 by Rev, Fr, Jorge Bellosillo of Immaculate Conception Quasi Parish.

        There were 430 first year and 210 second year, a total of 640 initial numbers of students who enrolled with 21 teachers.

        At the start of classes, the rooms were bare, no school decks, no blackboards. Some students brought their own stool for them not to squat on the floor. The needs of teachers and students were aired on television and printed on new page; thus, for the DECS to reciprocate and provide the basic classroom facilities.

        The 2000's marked more improvements. Additional chairs and tables were received. Facilities and equipment were improved. Computers were forwarded through the initiative of Councilor Bobby Eusebio. Special rooms were organized: Audio-Visual, Computer Room, EMIS, Science Laboratory and T.H.E. Learning Center. The office of the administrator was air-conditioned. The third year level was opened in S.Y. 2000-2001. By then, student population reached 1,033.'

        As the student popuace kept growing, there was a need for additioinal classrooms. In the year 2001, two new buildings were constructed, the SCE I and DPWH. This was the time when fourth year class was organized.