The first secondary school in the province of Rizal known as the Pasig Secondary School was established in 1902 during the incumbency of Governor Ambrosio Flores with an enrollment of 28 pupils. The students came from five neighboring towns including Pasig. The enrollment increased to 45 pupils in November, 65 in December and 88 in January and February in 1903, all intermediate pupils. The pupils were taught in a room of a rented building, 30 meters by 30 meters. The cost of the rent was $15, local currency, the amount paid from the provincial fund.