Santosh Kumar belongs to a district from Patna. His hobbies are swimming and playing cricket. He has completed his graduation from Magadh University and postgraduation in Rural Studies from Patna University. He started his career as a community teacher in Patna with slum children. He has been working at Pratham for the last 21 years. Over this period, he has been associated with the various programs run by Pratham and research conducted by ASER Centre. Currently, he is working at ASER Centre and is the Research Manager in Jharkhand.