The US President broke his own rule as once he said in a speech that a President couldn't wear anything on his head when he was offered a helmet while visiting the Army and Air Force football teams, E! Online reported.
The picture of annual White House Science Fair, was taken in June, but had recently been posted on Instagram by Pete Souza, the White House photographer.
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Souza said that Obama was convinced by the kids from Girl Scout Troop 2612 to wear a tiara with them for their group photo.