Educate from birth:

Language acquisition is inversely proportional to age (with a massive decline at puberty). Thus total cultural and language emersion starts at birth. Ending (without interruption if possible) at puberty.

After birth using talking dolls, robots and holograms, initial education is relatively unobtrusive.

As mobility occurs (1-2 years old) polyglot aids such as the vehicle, clothes and animals are utilized.

In preparation for secondary studies in the real world, a fantasy 10-19 cultural experience will need to be created. Using tents, warehouses, boats, islands or a mixture, depending on location (3-13 years).