Right - Medical School WW1-wartime collar year insignia, with three white bars.
A Medical School Student with five-cuff chevrons (pre-1908) /collar bars,indicating a fifth-year student.
Right - Extracted from a US Library of Congress photograph of two students (a first-year, and a second year-student, as indicated by the cuff chevrons in 1900), at the "Imperial High School Sam-i Serif Mekteb-i İdadi-yi, Damascus". However, more correctly these are students at the Military Secondary Schools. Education at the Military Secondary Schools, prepares the students for entry into the Imperial Army, graduating to go onto the Military School, to be trained as officers.
Right - From WW1, the white armband suggests one of these military secondary school students has been employed with the Ottoman Red Crescent Society; photographed in the Australian War Memorial picture B02833, taken in "Syria: Damascus 1918"). The keffiyeh was widely worn throughout the Ottoman empire.
The start of Scouting in Turkey is attributed to the brothers Ahmet and Abdurrahman Robenson. They were sports teachers at the Galatasaray, and Kabatas high schools in Istanbul in 1909; and Nafi Arif Kansuand Ethem Nejat.
The official history states, that "Scouting efforts were put to a halt during the Balkan Wars and World War I" .
Right - A photograph of the Ottoman prince Mehmed Orhan Efendi (b.1909), and taken in 1916-18 (when he was likely 7 or 9 years old). He is wearing a hight quality complete post-1916 Ottoman army officers' uniform. It is likely the case, he was in the Corps des Pages as these boys wore standard imperial army uniforms.
In WW1, the Ottoman Boy Scouts were used as the basis for a re-established Corps des Pages, at the Imperial Court's Palace School (school for pages training; as well as traditionally the education of 'white eunuchs').
Right - Extracted from the photograph collection of Charles Chusseau-Flaviens, a French independent photojournalist includes a series taken of the Ottoman Boy Scouts around the period of 1910 (but more likely from 1914, as the picture series were catalogued in 1919) . These show uniformed groups wearing:
 Illustrating the connection with the Ministry of War, most of Charles Chusseau-Flaviens photographs of the Ottoman Boy Scouts/Corps des Pages were taken in the grounds of the Ministry of War buildings, and prominently show the Beyazıt Fire Tower at the Gate of the Ministry of War.
 1916 Handbook of the Turkish Army', which describes the WW1 role of the Ottoman Boy Scouts movement, and its development/re-establishment of the Corps des Pages: