What is PISA? Does it help your college application?

A friend of mine is a pretty smart guy but doesn’t score incredibly high grades.

To my understanding, his grades dropped off around the eleventh grade before which he would regularly score around the 90 percent mark (Indian curriculum ICSE btw).

The other day, the guy receives an award for ranking 7th in the country for some test called PISA which he doesn’t even remember giving. Today he was talking about how he has a fair shot at a good UC or even an ivy if he raises his grades, finishes his drums course and writes a good college essay.

I don’t really know much about the application process, but does this test really matter this much???
Or more likely, is my friend just stupid?

PISA is a test organized by OECD to compare quality of secondary education across member nations/regions (mostly developed nations), and only for 15-year olds and only carried out once every few (3?) years. It has nothing to do with college applications/admissions (at least in this country)

PISA is an international test kids take at random - a whole cross-section of pupils from the entire country . It proves he’s an analytical, creative thinker with remarkable problem-solving skills. It’s possible your curriculum doesn’t call on his skills and may rest on memorization or repetition.
It’s nice for your friend and a great award to have…but it doesn’t mean he can apply anywhere.
Also, UCs have a wide range of acceptance rates from UCB/UCLA (highly selective) to UCM (selective).
Ivies (and NESCACs, UChicago, Northwestern, Vanderbilt, etc) are about MUCH MUCH more than ‘raising grades’.