Two hundred years of children.
D001290:Attitude; D002648:Child; D002652:Child Behavior; D002662:Child Health Services / Q000266:history; D004493:Education / Q000266:history; D006262:Health; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D008017:Life Expectancy; D014481:United States