Kim's Game is a game or exercise played by Boy Scouts, Girl Scouts and Girl Guides, and other children's groups. The game develops a person's capacity to observe and remember details. The name is derived from Rudyard Kipling's 1901 novel Kim, in which the hero, Kim, plays the game during his training as a spy.
Kim's Game Wikipedia
In Kim, the game is called both the Play of the Jewels and the Jewel Game. Kim, a teenager being trained in secret as a spy, spends a month in Simla, British India at the home of Mr. Lurgan, who ostensibly runs a jewel shop but in truth is engaged in espionage for the British against the Russians. Lurgan brings out a copper tray and tosses a handful of jewels onto it; his boy servant explains to Kim:
They contest the game many times, sometimes with jewels, sometimes with odd objects, and sometimes with photographs of people. It is considered a vital part of training in observation; Lurgan says:
This game is commonly played with young children, either preschool or in the first year or two of schooling (age 5 and 6) as it promotes the development of memory and observation skills and can be used for learning new groups of objects, such as shapes or fruits.
In his book Scouting Games Robert Baden-Powell, the founder of Scouting, names the exercise Kim's Game and describes it as follows:
The United States Marine Corps' Scout Sniper Instructor School in Quantico, Virginia, is one establishment that teaches the game as part of its curriculum. Another is Sniper training schools at Camp Lejeune, Camp Pendleton and in Hawaii. It is mentioned in a military glossary with the backronym "Keep In Memory".