Reach for Glory

Reach for Glory is a 1962 British film adaptation of John Rae's 1961 novel, "The Custard Boys", directed by Philip Leacock. It received a United Nations Award.
Plot.
A group of boys, evacuated during World War II from London to a coastal town, form a gang and play war games. Too young to fight in the war and afraid it will be over by the time they come of age, the group members, who are also in the school's Army Cadet Force initiate a battle with the local teenagers. Curlew, a local youth, invites an Austrian Jewish refugee with whom he has formed a close relationship to take part in the shenanigans. At first the Jewish boy, Stein, is scorned because of his "Germanic" heritage but is later allowed to join. When Stein runs off during a fight, the youths decide to give him a fake court-martial and execution, but real bullets are used by a freak mistake and Stein is killed.