Within months, though she only had one student, Watts had opened the Colégio Piracicabano and began by recruiting a French teacher, Marie Rennotte, in 1882.

The two women worked together to design an innovative co-educational learning environment, which offered courses in languages, literature, mathematics, philosophy, and the natural and physical sciences.

Though criticized by conservative sectors of society and the Catholic Church, Watts gained powerful supporters, including prominent progressive politicians, lawyers, masons, and abolitionists.

Watts remained at the Colégio Piracicabano for 14 years and then established three other schools in the states of Minas Gerais and Rio de Janeiro.

Ransom, wrote several letters to the Women's Board asking them to secure an American teacher who spoke French, without success.

[21] On February 23, 1882, Ransom reported to the Board that he had found a "French woman" with teaching degrees who had accepted an offer of employment.

Though the school term had already begun with 13 students,[22] Marie Rennotte, a Belgian teacher, did not join the staff until early March.

[25][26] Watts' approach to education was founded on Methodist ideology, which promoted a separation of church and state, individual and religious freedom, exploration of science and technology and democratic reforms aimed at producing faithful Christian servants to the nation.

[29][30][31] Providing a boarding school for girls, championing co-education and gender equality, Colégio Piracicabano offered a well-rounded curriculum, including courses in languages, literature, mathematics, philosophy, and natural and physical sciences.

[32] Though their curricula was approved of by progressive factions of society, the conservative elements, and specifically the Catholic Church, were harsh critics of Watts and the education provided by Colégio Piracicabano.

Nonetheless, by 1883, the enrollment had reached 30 students[33] with the support of abolitionists,[Notes 1] masons, and progressive politicians like Prudente Morais Barros (brother of Manuel),[36][37] who would become governor of São Paulo and President of Brazil.

In her absence, the school was run by Mary Bruce,[43] as Rennotte was also abroad gathering textbooks and class materials in Europe.

[43] Reaction was swift, with prominent local newspapers and the press in Rio de Janeiro, publishing denouncements of the inspector's actions.

[49] As the school was somewhat remote and in the mountains, it gave relief from the heat and epidemics that often occurred in Rio de Janeiro at the time, allowing diplomats and officials in the nearby capital to send their daughters there for safety.

[53] The Colégio Piracicabano was eventually transformed into the Methodist University of Piracicaba in 1975, after having expanded its curricula to offer tertiary courses in 1964.

[63] The Centro Cultural 'Martha Watts' (Martha Watts Cultural Center) located on Rua Boa Morte in Piracicaba was established in 2003 and pays homage to her "ações que visavam transformar as pessoas, seus costumes, seus hábitos, suas crenças levando-as ao desenvolvimento, tanto intelectual como espiritual" (actions aimed at transforming people, their customs, their habits, their beliefs—leading them to both intellectual and spiritual development).