Friedrich Wilhelm Froebel
Froebel holds a great amount of influence in education today. Called the "Father of Kindergarten," he created the idea of a curriculum, educational methodology, and teacher training. Each of these are still greatly used in not only Kindergarten, but all grade levels today! Froebel opened his first Kindergarten in Germany in 1837. In it, the students were given activities that allowed them to learn as they were ready- yet another educator influenced by the Naturalism approach!
For more on Froebel's first kindergarten, click the link below!