As I understand it many people are leaving rural areas to find work in cities. Cities are growing faster than governments ability to build infrastructure. Families have occupied land surrounding cities with out permission and so have no services. It is a no mans land of shacks, dirt roads, borrowed electrical lines strung up like spaghetti and open sewers.
Still lives go on - many children live in these unofficial neighbourhoods. You asked about organizations: I volunteer for an organization called Cada Niño Una Sonrisa. This month we worked on a school in one of these areas of Veracruz - we built girls and boys bathrooms, repaired the roof, got a modem and two computers, did general landscaping. I had a team of boy scouts, The teachers and several parents worked their butts off and, yes, there were several teens outside the fence drugged and belligerent. It made me realize what the kids go through to come to school each day.