Contrary to popular belief, Albert Einstein did not fail mathematics in school. The myth may have become popular when “Ripley’s Believe it or Not!” published the idea in its newspaper column in 1935. Today, this “false fact” turns up in many books and thousands of online references.
When shown told of the rumour, Einstein was amused; “I never failed in mathematics,” he replied. “Before I was fifteen I had mastered differential and integral calculus.” In elementary school, Einstein was at the top of his class in math. By age 12, he was able to solve complicated problems in applied arithmetic and began learning geometry and algebra on his own. Einstein also tackled new mathematical theories and even came up on his own with a way to prove the Pythagorean theorem. (Time Magazine)