Twelfth grade
Twelfth grade, Senior year, or Grade 12 are the North American names for the final year of secondary school. In most countries students then graduate at age 17 or 18. In some countries, there is 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.
Australia
In Australia, the twelfth grade is referred to as Year 12. In New South Wales, students are usually 16 or 17 years old when they enter Year 12 and 17–18 years during graduation (end of year). All students in Year 12 work towards getting an ATAR (Australian Tertiary Admission Rank) or OP (Overall Position, which applies only to students in the state of Queensland), which will allow them access to courses at university. In South Australia, this is achieved by completing the SACE; in Victoria, this is achieved by completing the VCE; in the Australian Capital Territory, this is achieved by completing the AST and in New South Wales this is achieved by completing the HSC.