Arne Starkey Duncan (born November 6, 1964) is an American educator and was a United States Secretary of Education from January 2009 through January 2016. While his tenure as Secretary was marked by varying degrees of opposition from both social conservatives and teachers unions, he nevertheless enjoyed strong support from the US president who appointed him, Barack Obama. Conservatives and some parents resisted Duncan's push for all U.S. states to adopt the Common Core Standards to determine what students had learned, and most US teachers unions disliked his emphasis on the use of data from student tests to evaluate teachers and schools. Despite antagonism to the changes Duncan had introduced, Obama praised his work at the Department of Education by saying, "Arne has done more to bring our