Can You Test Out of High School?

Is there a test students can take to get out of high school early if they are still not 17 or 18?
Students can take the California High School Proficiency Exam (CHSPE) if they are at least 16 years old and have been enrolled in the 10th grade for one calendar year. If a student passes the test, they are given a certificate of proficiency which is the equivalent of a high school diploma and this student is not considered a dropout. Students are only allowed to leave school early if they pass this test and have verified parent approval.
 posted by Jane