The sum total of 13 years of learning will be boiled down to the rough handful of study scores that inform their Australian Tertiary Admission Rank.

This is the ATAR. It assigns each student's ranking, compared with all other VCE students in 2017, rendered as a percentile. In the gruelling marathon that is Year 12, the student with a 99.00 has achieved results that put them in the top one per cent. The student with an ATAR of 50.00 has not 'barely passed', but is simply further back in the pecking order.

A school's median ATAR is closely studied by principals and parents; ATAR medians above 80 are cited as signs of academic excellence.

But the ATAR does not tell us that much about the skills a student has acquired and nowhere near enough about a school's ability to teach.

A good study score in, say, Further Maths, does not prove the student understands the difference between nominal and effective interest rates, or how this knowledge could be used. It simply demonstrates that student A performed better than other students who sat the same test, even if all of them mastered the basic concept or none of them did.

This is one of the reasons why many universities use interviews and folios when considering applications - some tertiary courses bypass ATAR scores altogether, and have offered places directly to students who impress at interviews.

There is considerable hand-wringing over slipping standards at tertiary level. Indeed, the "clearly in" ATAR cut-offs published by universities now serve as a kind of stock market where the exchange rate is based on course demand - an increase in the ATAR cut-off indicates a surge in the stocks of nursing degrees, a low-ranking cut-off for IT courses suggests coding jobs have been shorted by students cautious about job prospects.

A business that merely ranked all its employees from 1-100 would not know what their employees could already do or needed to learn. And yet our entire tertiary admissions system is this opaque.

Education reformers have long been campaigning for clearer reporting of the student skills, from the ability to read a picture book in early primary to problem solving in middle years to sophisticated analysis in year 12. Some study designs for VCE subjects require students to demonstrate these higher order skills under exam conditions, but nobody will ever know for sure, because the exams themselves, and the real marks, are never seen - unless the student pays to get the exam back.

It is too glib to tell the class of 2017 that "the number does not matter" when this is all the current system provides them in exchange for their efforts. It could be argued that completing VCE equips students to knuckle down to complete hellish workloads under punishing deadlines under high stress - conditions they may face in many future workplaces.

But their hard work demands reforms that help students - and their future teachers and employers - measure the skills they've learned in practical and transparent ways.

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