Arizona crowd sings 'Happy Birthday' to Obama

Visit for breaking news, world news, and news about the economy

Students at Desert Vista High School began singing shortly after Obama warned the senior class not to get complacent in their final year.

The president grinned through the song, which slowly gained momentum until much of the crowd joined in.

"I'm now 52 and Michelle says I don't look a day over 51," the president joked.

Obama's actual birthday was Sunday, and the president spent the weekend with a round of golf at Joint Base Andrews with friends and a retreat to Camp David.