Nigeria, the tenth largest country globally and the fourth largest economy in Africa, lies on the west coast of Africa and occupies approximately 923,768 km2 of land bordering Niger, Chad, Cameroon, and Benin. Nigeria is the most populous country in Africa, with a population of 140 million (NPC, 2006) and one of the ten mega countries in the World Health Organization (WHO) mega country school health project. One out of every five Africans is a Nigerian. About 64% of the population lives in rural areas with the balance of 36% living in urban areas. About 70% of the population is under the age of 30 while those under 15 make up 44%.