School reunions are usually either events to totally avoid, or ones to grin and bear.

Most school reunions, however, don't have one of the world's best-known rock musicians playing at them.

Eddie Vedder was playing a secret fundraising show for his former high school San Dieguito Academy in Encinitas, California, and with many of his former classmates in attendance it soon turned into an impromptu high school reunion.

Some of them even hopped onstage to jam a few songs with the Pearl Jam frontman, including 'Roadrunner' by The Modern Lovers and 'Got the Time' by Joe Jackson.

Watch footage below: