12th grade is the final year of secondary school.
12th Grade is the final year of secondary school, but did you continue and attend college? 
yes i did. you? Most countries student graduate at age 17-18.
I attended a technical college and studied Cosmetology. Here in the US we graduate at 17-19 depending on birth date.
Twelfth grade
Twelfth grade, senior year, or grade 12 is the final year of secondary school in most of North America. In other regions it is also equivalently referred to as class 12 or Year 13. In most countries students then graduate at either ages 18 or 19. Some countries have a thirteenth grade, while other countries do not have a 12th grade/year at all. Twelfth grade is typically the last year of high school; graduation year.
Australia.
In Australia, the twelfth grade is
college.
Newfoundland and Labrador did not introduce Grade 12 until 1983.
Denmark.
In Denmark, the twelfth grade is the 3rd G, which is the final year of secondary school. 3.g is equivalent to 3rd grade of secondary school, or gymnasium. This is not compulsory, as education is only compulsory through 9th grade. Students are often 18-19 or older when they finish secondary school. The age of graduation is caused by the fact that Danish children first start school at 6. The reason that