By Paul Virr. Meet history's game changers! This biography series is for kids who loved Who Was? and are ready for the next level. Albert Einstein is the most famous scientist of all time. His theories form the basis of physics today. Find out how the boy who taught himself calculus at age twelve became one of history's greatest trailblazers! Trailblazers is a biography series that celebrates the lives of amazing pioneers, past and present, from all over the world.