City of Liberty is a huge campus of schools and colleges, ranging from kindergarten to university – and if you suddenly discover that small stones and pebbles are being thrown at you as walk past one of the playgrounds then you're probably walking past the School for the "behaviourally disturbed", one of several specialist schools also located there.
The City of Liberty was formerly an Army base, parade grounds, and was the residence for the dictator Fulgencio Batista (who moved there for security reasons). It was turned into a centre for educational facilities after the revolution in 1959, and it is now full of lots of young, bright, eager, and playful kids.