Preschools provide education from ages approximately three to seven, depending on the country, when children enter primary education. These are also known as nursery schools and as kindergarten, except in the US, where kindergarten is a term used for primary education.[citation needed] Kindergarten "provide[s] a child-centered, preschool curriculum for three- to seven-year-old children that aim[s] at unfolding the child's physical, intellectual, and moral nature with balanced emphasis on each of them."
 What are pre-schools not known as?