Gradually he pieced together a "blueprint" for normal cognitive development in children ... the toy still existed. Piaget found four major developmental stages (with many subdivisions).

By thinking that children have great cognitive abilities, Piaget came up with four different cognitive development stages, which he put out into testing. Within those four stages he managed to group ...

Jean Piaget's ideas about child development continue to influence pedagogical practices around the world. His pioneering work ...