The Atlantic has a piece about the German practice of putting away toys in kindergarten for a period in order to encourage children to learn to rely more on their own imaginations and social abilities when they play– and develop the inner resources to resist addictions later in life.

It grew out of an addiction study group… in the 1980s. The group included people who had worked directly with adult addicts and determined that, for many, habit-forming behavior had roots in childhood. To prevent these potential seeds of addiction from ever being planted, the researchers ultimately decided to create a project for kitas and kindergartens, which in Germany typically serve children ages 3 to 6, and remove the things children sometimes use to distract themselves from their negative feelings: toys.