The first Mariinsky school was opened in
Saint Petersburg in March 1858. The school was championed by the Russian educator and supported by the
Duke Peter of Oldenburg. It was an experimental school that admitted girls regardless of their social class (noble girls could attend one of the
Institutes for Noble Maidens). After two years, the school was reorganized into Mariinsky Gymnasium and similar schools quickly spread throughout the empire. In 1862, there were 12 Mariinsky Gymnasiums. The number grew to 25 in 1867. The curriculum included religion, Russian language and literature, French and German languages, history, geography, natural science, arithmetic and geometry, the basics of pedagogy, calligraphy, drawing, singing, needlework, dancing. Many graduates received certificates of home tutors (private teachers). The schools were mainly funded by tuition fees which, on average, comprised about 70% of the budget. They received about 13–16% of their revenue from the Office of the Institutions of Empress Maria. According to the charter of 1862, girls of all religions, including Jewish, and social classes could attend the Mariinsky gymnasiums. During the second half of the 19th century, the proportion of children of urban classes gradually increased (from 27.3% to 36.5%), and the number of noblewomen decreased (from 54.3% to 50.2%). ==List of schools==