Most children enter the public education system around ages five or six. The American school year traditionally begins in August or September, after the traditional summer recess. Children are assigned into year groups known as grades, beginning with preschool, followed by kindergarten and culminating in twelfth grade. Children customarily advance together from one grade to the next as a single cohort or "class" upon reaching the end of each school year in May or June, although developmentally disabled children may be held back a grade and gifted children may skip ahead early to the next grade.
The American educational system comprises 12 grades of study over 12 calendar years of primary and secondary education before graduating and becoming eligible for college admission. After pre-kindergarten and kindergarten, there are five years in primary school (normally known as elementary school). After completing five grades, the student will enter junior high or middle school and then high school to get the high school diploma.
The U.S. uses ordinal numbers for naming grades, unlike Canada and Australia where cardinal numbers are preferred. Thus, Americans are more likely to say "First Grade" rather than "Grade One". Typical ages and grade groupings in public and private schools may be found through the U.S. Department of Education. Many different variations exist across the country.
Students completing high school may apply to attend an undergraduate school. This may be a community college (one that offers two-year degrees, usually to prepare students to transfer to state universities), liberal arts college (one that concentrates on undergraduate education), or part of a larger research university.
The course of study is called the "major", which comprises the main or special subjects. However, students are not locked into a major upon admission—usually, a major is chosen by the second year of college, and changing majors is frequently possible depending on how the credits work out, unlike British tertiary education. Universities are either public (state-sponsored, such as The Ohio State University or University of Georgia) or private such as Harvard or Swarthmore College.
Students may choose to continue onto graduate school for a master's or Ph.D, or to a first professional degree program. A master's degree requires an additional two years of specialized study; a doctoral degree (Ph.D.) usually takes some years, although exactly how long depends on the time required to prepare the doctoral dissertation. First professional degrees have a more structured program than the typical Ph.D. program. The standard time required for a first professional degree is three or four years; for example, law school is a three-year program, while medical, dental, and veterinary schools are four-year programs.