In 1834, as it is known, the capital of the Greek state was transferred from Nauplion to Athens and the intellectual activity of the country followed suit.

Thus, by governmental decree, the Central School of Aegina was moved to Athens on April 10, 1835 and was given the new name “Gymnasium”-. Georgios Gennadius was its first principal. The housing of the institution proved problematic, since most Athenian houses were judged unsuitable. Finally, a house situated on the northern foothill of the Acropolis was selected. When exactly this house was built is unknown, Solon Kydoniatis believes that it was sold by its owner Sante Chanum to the architect Stamatis Cleanthes in 1831. Soon after it was sold, the house was renovated by Cleanthes and his colleague Schaubert. It is characteristic that while the Greek scholars refer to the house as “ the house of Cleanthes”, their German counterparts call it the “house of Schaubert”. Nevertheless, this was the edifice that housed the First High School of Athens. In the archives of the present First High School of Plaka, Gennadius’ book of “correspondence and various other contents” is kept until today.

The information supplied from it proves that from 1835 until October of 1836 the house of Cleanthes was used as a school. The increasing number of students caused a new transfer of the school that was moved to the house of Votsaris, this time, on October 12, 1836. A few months later the institution of the University was decided. Two houses were then proposed for its housing, the house of K. Vlachoutsis and the house of Cleanthes. The second was, finally, selected.