High school senior

Twelfth grade, senior year, or grade 12 is the final year of secondary school in North America. In other regions it is also equivalently referred as class 12 or Year 13. In most countries students then graduate at age 17–18. 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.

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.

In New South Wales, when completing the [HSC], students are required to satisfactorily complete at least 10 units of study in ATAR courses which must include:

Some Year 12s may receive a Year 12 Jersey. Schools choose the design, colours and writing which are printed or stitched onto the jersey. Sometimes the last two digits of the year they are graduating are printed on the back (for example, "12" for 2012 school leavers) along with a personalised nickname. The front may show the school emblem and the student's name, which is occasionally stitched in.

Many schools conduct end of year "formals" (similar to a senior prom). They are held from any time between graduation in September to November.

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