Pohwasogeuro aka 71: Into the Fire (2010)

http://www.imdb.com/title/tt1587729/

5/5

A true story of a group of 71 undertrained and undergunned student-soldiers for South Korea during the Korean War, who were mostly killed on August 11, 1950, during the Battle of P'ohang-dong, while defending P'ohang-dong girls' middle school, a strategic point for safeguarding the Nakdong River, from an attack by overwhelming North Korean forces for 11 hours.