Sir Paul McCartney went back to school today as he received an honorary degree from one of America's top universities.

The Beatles legend was the guest star at the graduation ceremony of prestigious Yale University in New Haven, Connecticut.

Sir. Paul donned traditional black academic robes and carried his mortarboard hat as he received a Doctor of Music Award at the Ivy League school.

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Top honour: Macca was awarded a doctorate for services to music at prestigious Yale University in New Haven, Connecticut today

More than 1,000 students, who packed into the university's Old Campus area, cheered on Macca and applauded as he appeared on the outdoor stage.

McCartney, who received a pink academic sash, smiled and clapped graduates as they received their degree diplomas.

And he could even be seen singing along to a series of hymns that were played during the hour-long ceremony.

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Proud: Macca proudly shows off his certificate after being awarded the honour at Yale University

McCartney even posed for some students as they took pictures of him sitting with leading academics on stage.

Sir Paul, who did not speak during the event, was one of eight people to receive honorary degrees at the university's 307th annual Commencement.

The 65-year-old musician's appearance at the university came one day after Tony Blair gave a speech at his son Euan's graduation.