Parasitic worms infect over 1 billion people in the developing world today, yet the treatments are inexpensive. For people infected with worms, taking these medications can improve school attendance and performance, but little is known about the long-term gain from de-worming treatment early in life. In my study this summer, I aim to collect data to answer exactly that question, in the context of de-worming interventions that took place in East Africa from 1998-2001.