Bev Bos coined this phrase: The child is the curriculum.   That really defines child-centered teaching & learning.   We learn so much about our children when we interact with them and let them choose what they want to do in the classroom.    I like to define "curriculum" as 'everything that happens in the classroom'.    "You can discover more about a person in an hour of play than in a year of conversation"   - Plato  from   http://www.playcounts.com/