when there is a time table for each year group so that kids get 2 or 3 subjects a night, supposed to be half hour each (obviously some set a longer homework lasting several weeks), and they nag (quite rightly) about not stocking it all up till the last night, then the teachers should stick to the right night and not give homework out willy nilly or say they will give it out next time.
OK if it works in the kids' favour so they get more time and can plan their work better, get it out of the way sooner, but totally unfair when it puts them under pressure to do that PLUS their allotted subjects overnight (meaning their other homework may be of lesser quality due to time constraints)