Pop Warner Little Scholars, commonly known simply as Pop Warner, is a nonprofit organization that provides activities such as American football, for over 425,000 youths aged 5 to 16 years old, in several nations. It is the largest youth football organization in the United States. In the 2010s, concern grew about the dangers of brain injury, including that from a steady diet of sub-concussive hits. There have been proposals to replace tackle football with flag football below certain ages.