Hans Freudenthal (17 September 1905 - 13 October 1990) was born in the German town of Luckenwalde, the son of a Jewish teacher. Even at a young age, he was interested in differential equations and integration, but by the age of 13 he had also read all the works of Goethe and Schiller. In 1923, he went to Berlin and Paris to study mathematics. After gaining his doctorate, he moved to Amsterdam, in the Netherlands, where he became assistant to L.E.J. Brouwer (1881-1966), the famous mathematician, in 1930. Shortly after, he married Susana (Suus) Lutter, who was a pedagogue. Thanks to his marriage to a non-Jewish Dutchwoman and a certain amount of luck, Freudenthal was able to survive the Second World War. In 1946, Freudenthal became a professor in Utrecht, appointed to a chair in pure and applied mathematics and the principles of mathematics.

In his time, Freudenthal was an accomplished and well-known mathematician, and he made substantial contributions to topology, geometry and the theory of Lie groups. As a teacher, he acquired international fame and significance as the founder of Realistic Mathematics Education, which is based on problems taken from day-to-day experiences rather than on abstract mathematical rules. Single-handedly, Freudenthal kept Dutch mathematics education away from the New Math, which was introduced in many countries from 1960 onwards.

Freudenthal preferred to send his students on a tour of discovery. His motto was that you learn mathematics best by re-inventing it. His students were not given abstract bare problems to do but well-chosen practical problems from daily life, and in solving these, they gradually developed mathematical understanding. In addition, Freudenthal thought the recognizability of the problems would lead to the students to become more interested in mathematics.

He served as the eighth president of the International Commission on Mathematical Instruction from 1967 to 1970. In 1971 he founded the Institute for the Development of Mathematical Education (IOWO) at Utrecht University, which after his death was renamed as the Freudenthal Institute, and is now the Freudenthal Institute for Science and Mathematics Education. In 1968 he founded the journal Educational Studies in Mathematics, which is considered one of the two most prestigious journals in the field. In 1972, he founded and became editor-in-chief of the journal Geometriae Dedicata, devoted to geometry and its relationship to topology, group theory and the theory of dynamical systems. He retired from his professorship in 1975.