Reopening a school in the capital, she operated until the Spain ceded the country to the United States and the educational authorities changed the requirements, implementing English language curricula.

The school was the first non-parochial institution in the country and based its curriculum on a modern, liberal model, attempting to equalize the education of girls with what was offered to boys.

[2] Her father, an intellectual, worked in a pharmacy and also operated a store which sold sundries,[3] including fabrics, needles and thread, cigars, and other items.

[5] Though her early education began at home, from five or six years old, Avelino, who was called "Ada", was sent to the public girls' school run by Luisa Bacho.

[8] As Avelino wanted to learn more than was typically offered to girls, Maestra Bacho instructed her in rudimentary domestic science, geography and Spanish grammar, and introduced her to more difficult mathematical studies.

[9] She also studied advanced syntax and language with Fermin Raymundo, a local Spanish grammarian, as well as music, including the piano, with Ladislao Bonus.

After completing the courses in 1889, Avelino faced a jury and successfully passed the civil exam for elementary school teachers,[12][13] becoming the first woman to receive certification in the Spanish era.

[19] Activities at Avelino's school initially continued at the onset of the Philippine Revolution in 1896,[20] but when the United States forces arrived in Pandacan, she suspended her courses.

[13][14] Simultaneously, she studied in the mornings with an American teacher, while also taking night courses in Sampaloc with tutor Mauricio Somosa to enhance her language skills.

[31] Securing his approval, she closed the school and accompanied the Gonzalez family to Hong Kong, where she studied for half the year, but had to return due to illness of one of their party.

Still longing to open a school, when she came out of mourning in 1907,[35] Avelino sought the advice of Fernando Salas, a lawyer from a family of educators, and her friend Carmen de Luna.

[42][39] Having little capital, but wanting to establish a modern, liberal school, Avelino approached educated women like Maria del Pilar Francisco, the first woman lawyer in the Philippines; Felisa and Domingo Francisco, cousins of Maria; sisters Filomena and Ildefonsa Amor;[43] her cousin Garit Oliva; and Constancia P. Arrieta, all having graduated from Normal School.

[51] As one of the leading feminists of the period,[13] when Carrie Chapman Catt and Aletta Jacobs visited the Philippines in 1912, Avelino met with them during one of their scheduled stops.

[53] Around 1917, they moved to a newly built facility located at 2265 Azcarraga Street with over 650 students[54] and by 1920 the school was the largest women's institution in the country.

[58] Because of the inability to secure a hospital facility for students to gain practical experience, the government withheld accreditation of the Medical College, which was forced to close after four years of operation.

[13] There are memorials throughout the country which honor Avelino: a street in Pandacan bears her name,[66] as does an elementary school in Tondo;[67] and an auditorium and statue at the Centro Escolar University.