Kim’s game is an exercise to improve the memory. The game has since been immortalised by the boy scouts (who tend to play with camping items, rather than precious gems).
Kim's education with Lurgan has prompted much debate around Kipling’s attitudes towards Eastern versus Western thought. Kim fights Lurgan’s attempts at hypnosis by reciting his maths times-tables, learnt at St Xavier's. By having Kim resist the powers of illusion and develop great skill at the memory game, Kipling is arguably implying that the once rebellious street urchin has absorbed a Western regimented style of thinking.