On Leontievsky Lane at the corner with Swedish Dead End, a building in Scandinavian style appeared in 1893, designed by architect D.N. Chichagov. The lane got its name due to the Swedish Courtyard, which was located here in 1618 and 1874, despite interruptions due to wars. In 1874, the land of the courtyard was exchanged for a plot in Stockholm, owned by Russia, where warehouses for Russian merchants were located.

In 1892, merchant Alexander Sergeyevich Kaptsov donated 190 thousand rubles for the construction of a city primary school named after his father, Sergey Alexandrovich Kaptsov, designed for 200 boys. With this funding, a gymnasium building was constructed in the "Christina IV" style, characteristic of the architecture of the Danish Rosenborg Castle and the stock exchange in Copenhagen.

After the death of Kaptsov's mother, Ksenia Vasilievna, in 1896, architect Geppener added a women's department for 300 girls to the gymnasium from the side of Bolshoy Gnezdnikovsky Lane.

The Kaptsov family, starting from the mid-19th century, owned a large silk goods store in Kitai-Gorod and lived in a mansion on Vorontsovo Pole Street, built in 1888 by the same architect Chichagov. The Kaptsovs actively supported the gymnasium, financing it until 1917. After Alexander Sergeyevich's death in 1897, his wife Anna Mikhailovna, owner of a silk weaving factory in Fryazino, took over the management. She founded the Partnership "Anna Kaptsova with Sons," which successfully operated until the revolution. Her son Mikhail became the first dealer of the "Opel" factory in Russia and opened a taxi park in Moscow.

After the 1917 revolution, the gymnasium was transformed into school No. 31. Two schools were located in its premises: No. 131 and No. 119. During the war, school No. 131 was evacuated, and the building of No. 119 housed a hospital and a reconnaissance school of SMERSH. From 1943 to the 1950s, school No. 131 was a girls' school, with graduates including Lyudmila Tselikovskaya and Yulia Drunina.

After the war, school No. 31 became one of the best special schools with an in-depth study of the English language. In 1952, the building was extended, the high pediments were removed, two floors were added, and a new facade was created, but the internal layout remained the same.

In 1993, the school was renamed Gymnasium No. 1520 after the Kaptsovs.