K-12

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. The expression is a shortening of kindergarten (K) for 4- to 6-year-olds through twelfth grade (12) for 7- 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 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.

It is also used by American multinationals selling into the educational sector, such as Dell where UK customers are presented with this as a market segment choice.

In Australia, P–12 is sometimes used in place of K–12, particularly in Queensland, where it is used as an official term in the curriculum framework. P–12 schools serve children for the thirteen years from prep until Year 12, without including the separate kindergarten component. In Canada (Nova Scotia) P–12 is used commonly in place of K–12 and serves students from grade Primary through 12.

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