Freshman, sophomore, junior, senior are the names for the high school grades 9-12. Kindergarten is usually for children 5 or 6 years old; 1st grade, 6-7 years

Freshman, sophomore, junior, senior are the names for the high school grades 9-12. Kindergarten is usually for children 5 or 6 years old; 1st grade, 6-7 years old, etc. By 12th (senior) year of high school, kids are usually somewhere between 17-19 years of age.