The US education system follows a pattern similar to many systems around the world. Early childhood education (pre-kindergarten) is followed by five years of primary school which is called elementary school in the US. The next stage is three years of middle school, and four years of secondary school called high school, and then postsecondary (tertiary) education. Primary to high school education is completed in 12 years and is known as K through 12 or K-12.
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