Alexandros Delmouzos served as its first supervisor, and Vasilios Tatakis, a well known scientist, was the first Head of School.
During the World War II, the school stopped operating while in the years of the Nazi occupation of Greece, it ran under very difficult circumstances.
During the difficult years of the Nazi Occupation and the Greek Civil War that followed, Xirotiris protected many faculty members from prosecution.
He was unfamiliar and indifferent to the ideas and values that the school represented, therefore his ideology and attitude suited the zeitgeist of his era.
Some of them, when they were summoned to testify in their defense, mentioned the Experimental School, showing how proud they were for their education there.