Primary education in the United States

Primary education in the United States (also elementary education) refers to the first eight years of formal education in most jurisdictions, often in elementary school. Preschool programs, which are less formal and usually not mandated by law, are generally not considered part of primary education. The first year of primary education is commonly referred to as kindergarten and begins at or around age 5. Subsequent years are usually numbered being referred to as first grade, second grade, and so forth. Students graduating from fifth grade, typically the last elementary year, are normally age 11.
In 2001, there were 92,858 elementary schools (68,173 public, 24,685 private) in the United States.
Preschool
Some private schools, and some public schools, are offering pre-kindergarten (also known as preschool or pre-K) as part of elementary school.[citation...