My two cents: I grew up in the Netherlands. My schooling: six years elementary, four years 'high school', that of course ended 52 years ago for me so things there may have changed.
No homework EVER in elementary school. After elementary school we knew we were 'growing up' and expected homework and did it.
With my boys here in the US I saw homework the very first day of first grade, at a time where kids just need to be kids and be allowed to play. By the time these kids get to middle school and high school they HATE and FIGHT homework.
I honestly, after five boys, have never seen the use for this 'forced child labor' in elementary school.
Like I said, my two cents.
2003 1800s, 88k miles