Teachers of science on all grade levels ask for guides to better curricula. The natural concepts give this direction. These concepts meet three criteria : (1) They inhere in all objects and processes. They define the structure and expression of nature. (2) They impel the questions of children; they belong to the play of infants‘ and solve their problems. ( 3 ) They unify the thrusts of man’s mind as told in the long history of science, for they uphold all of our scientific laws and principles. The natural concepts offer science education system, order, and harmony.