One of the major changes in educational practices occurred during the Italian Renaissance, when a system of pre-university education based on a thorough grounding in the Latin, and to a lesser extent, the Greek classics began. This change started in early 15th century northern Italy and lasted until well into the 20th century. Italian school children of the 14th century followed a normative medieval curriculum which consisted of reading such medieval authors as Donatus, Cato, and Theodulus. Although classical authors were taught along with medieval textbooks, they did not dominate. The early humanist scholars stressed the purpose and promise of humanistic education. Foremost among these scholars was Guarino Guarini of Verona (1374-1460). A handful of pedagogical pioneers won the support of a few political leaders who sponsored their local schools in a small region of northern Italy. Cicero's works became the most important texts in humanistic schools. By 1490 or 1500 the humanistic curriculum must have been universal in Italian schools. Humanistic studies then spread to northern Europe. (PPB)