The gymnasium began operation on the initiative of the Zagreb City Council, with the approval of the Croatian Parliament (Sabor) and strong support of Ban of Croatia Ivan Drašković.

The gymnasium official opened on June 3, 1607, in a ceremony attended by Bishop of Zagreb Šimun Bratulić, ban Ivan Drašković and others.

[1] In August 1942, the Zagreb police of the Croatian fascist, ultranationalist Ustaše regime arrested 1,200 Jews and held them in the Classical Gymnasium which was them empty because of Summer holidays.

The program, lasting four years, is based on combining classical education, with emphasis on humanities (namely languages including Latin and Ancient Greek, philosophy, literature, history, fine arts, music and theatre), with sciences and extracurricular activities.

They also study Croatian and World Literature, Mathematics, Physics, Chemistry, Biology, Geography, IT, History, Fine Arts, Music, Philosophy, Logic, Politics and Economy, Sociology, Psychology and attend exercise classes.