What is the age limit to finish going high school?

In most states, the maximum age to attend high school is 21 years old. However, some states have exceptions for students with disabilities or other special circumstances. For example, in some states, students who have not completed high school by age 21 may still be eligible to attend if they are "making satisfactory progress" towards graduation. Other states may allow students to attend high school until age 25 if they have a documented disability or other special circumstance.