Cuban soldiers receive combat training at the Cadets School “Antonio Maceo” November 28, 2001, 30 kilometers East of Havana. (Photo by Jorge Rey/Getty Images)

A group of Japanese schoolgirls marching in formation during a school visit to the third regiment to experience the soldier's way of life. (Photo by Fox Photos/Getty Images). Circa 1938

A member of the Eton public school O.T.C. (Officers Training Corps) practising shouting out orders during a training session, 20th January 1940. (Photo by Hulton Archive/Getty Images)

A design of Hongik University Seoul is displayed on July 19, 2011 in Maranello, Italy. The Ferrari World Design Contest has been launched by Ferrari in collaboration with Autodesk for 50 prestigious international design schools. The winners will win an internship at Ferrari. (Photo by Vittorio Zunino Celotto/Getty Images)

Pakistani female police commandos attend a training session in Nowshera, near Peshawar Pakistan, Wednesday, February 11, 2015. Authorities formed a Special Combat Unit after Taliban militants stormed a Peshawar school on Dec. 16, 2014 and massacred 150 children and teachers. (Photo by Mohammad Sajjad/AP Photo)

Ty, a 15-year-old boy, poses for a picture while collecting usable items at a landfill dumpsite outside Siem Reap March 19, 2015. Ty, who finished six-grade primary school, said he makes 5 USD per month working at the dumpsite. (Photo by Athit Perawongmetha/Reuters)

Californian photographer and conservationist Octavio Aburto had spent years photographing the school in Cabo Pulmo National Park, Mexico – and had been trying to capture this exact shot for three years. “Together with my friend David Castro, we were diving with a large group of Bigeye travellies at Cabo Pulmo National Park, Mexico. Thousands of fish forming a ball during the reproduction courtship. In the afternoon, these fish congregate to form a large spawning aggregation around the reefs of the National Park”. (Photo and caption by Octavio Aburto)