Overview
The term senior, in regard to education, has different meanings depending on the country.
United States
In the United States education, a senior is a student in the fourth year of study, either in high school or college/university.
High school
The twelfth grade is the fourth and final year of a student's high school education. The year and the student are both referred to as senior. Senior year is when most students take college entrance exams (ACT or SAT) and actually apply to college/university. A common stereotype of high school seniors in the Unites States is that they suffer from "senioritis", a perceived laziness or lack of motivation to complete schoolwork in this year. This is due to the assumption that colleges and universities place greater emphasis on a student's performance during junior year when making admission decisions, and that poor academic performance during senior year won't matter because the senior will already have been admitted to college at the time of graduation. Alternatively, senior year is when students decide to pursue a trade and enroll in a relevant school or program rather than attending college/university. Some seniors decide to put off higher education in favor of entering the work force.
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