India, April 18 -- LUCKNOW Barely clothed, a 4-year-old boy stands amid the ruins and fluently names parts of the human body in English. When prompted, he confidently recites the days of the week, from Monday to Sunday. His name is Rinku, and like many children here, his first lessons came not from a formal school, but from a makeshift classroom run by Manju Devi, 50, in Vikas Nagar's slum cluster that was ravaged by fire on Wenesday evening.

For nearly two decades, Manju's open-air school was the starting point of education for hundreds of children in the area. Teaching up to classes 4 and 5, she helped them learn basic reading, writing and arithmetic, skills that later enabled many to transition into government schools or even run smal...