K-12 schools

K–12 (spoken as "k twelve", "k through twelve", or "k to twelve") comprises the sum of primary and secondary education in the United States, Canada, South Korea, Turkey, Philippines, Egypt, Australia, India, Afghanistan and Iran for publicly-supported school grades prior to college . The expression is a shortening of kindergarten (K) for 4- to 6-year-olds through twelfth grade (12) for 17- to 19-year-olds, the first and last grades of free education in these countries, respectively. The related term P–12 is also occasionally used in Australia and the United States, to refer to the sum of K–12 plus preschool education.

The image at the right is a table that defines the education system in the United States. The table shows the progression of the education system starting with the basic K–12 system then progressing through post-secondary education. K–14 refers to K–12 plus two years of post-secondary where training was received from vocational technical institutions or community or junior colleges. The K numbers refer to the years of educational attainment and continues to progress upward accordingly depending on the degree being sought.

The term is often used in school website URLs, generally appearing before the country code top-level domain (or in the United States, the state top-level domain). The term "PK–12" is sometimes used to add pre-kindergarten.

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