> Even if the Finns don't need it, research suggests it makes a positive difference. Prof Susan Hallam from the Institute of Education says there is "hard evidence" that homework really does improve how well pupils achieve. "There is no question about that," she says. A study for the Department for Education found students who did two to three hours of homework per night were almost 10 times more likely to achieve five good GCSEs than those who did no homework

https://www.bbc.com/news/education-37716005

Finns appear to have a school system that works in a manner that suits their nation, and was reformed decades ago.

>A study for the Department for Education found students who did two to three hours of homework per night were almost 10 times more likely to achieve five good GCSEs than those who did no homework

It didn't control for why they were doing the homework. I'd bet if you did a study comparing two cohorts of students with identical social-economic status and IQ, you wouldn't see a significant difference.