The High School Musical star voices the character of Ted in the new film version of Dr. Seuss' classic book and he marked Read Across America Day on Friday by reciting the story to 300 kids at the New York Public Library in Manhattan.
He teamed up with his The Lorax co-star Danny DeVito for the reading, which also marked 108 years since the writer's birth.
Efron says, "As a kid, I remember thinking, 'What would it be like to go on this big adventure...?' Now here I am, two decades later, voicing Ted in Dr. Seuss' The Lorax,. It's an honour to not only be a part of this movie, but to work with the National Education Association's Read Across America to inspire the love of reading in millions of kids."