Americans go to school for 12 years (grades). At age 6, they start primary (or elementary) school. After this, they move on to secondary school which consists of 2 programs. The first program is middle school (a.k.a. junior high school, or just junior high). The second program is high school.
After graduating high school (12th grade), a diploma is granted and the students can move on to higher education as either college or university.

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