In the United States, 9th grade is the first year of high school, and students in this grade are called freshmen. The other three years of high school are called sophomore year (10th grade), junior year (11th grade), and senior year (12th grade) . These terms are also used in undergraduate education, where freshman year refers to the first year of college, sophomore year refers to the second year, junior year refers to the third year, and senior year refers to the fourth and final year.