The game "Secrets" was common among soviet children, in my childhood we also played this game. The essence of the game was to create your "secret" and hide it under a small amount of ground in a secret place. Pieces of glass were used to make the "secret", under them they put candy wrappers or a herbarium, etc. Sometimes children put things in the "secrets" that were of a certain value to them (for example, remember I once put a brooch).
You could show your "secret" to your best friend as a sign of trust.
Often some children ruined the "secrets" of other children. Apparently, the creation of "secrets", as well as their demonstration and sometimes ruin by other children, had a ritual meaning of self-expression and relationships.
