According to the United Nations, about two-thirds of the world's population will be living in cities by the next 30 years.
The World Health Organization recommends classrooms to be not louder than 35 decibels, which is never the case in big cities.
Children are facing disruption in their learning, and research points out that those who study in a noisy place are 11 months behind the ones who are studying in quieter places in the same vicinity.