One of the classes that I teach is comprised of 5 or so 6th graders, and, while they are nice and I like them, they are lazy.
Lazy--there is no other word to really describe them. As a group they often do not do their assigned homework, or only do part of it.
My Korean co-teacher and I were confounded about how to deal with them, so I talked with my school director, and we came up with a plan.
She told them that if they failed to do their homework then, the next class, they would have to stay an extra hour at our school.
So far the strict measure has only been applied to one boy, but I think the rule will be employed again as their summer vacation is affecting their homework attitude (our students are on public school vacation, but they still attend our--and other--private academies).
Normally we use the 3 X system . . . when a class gets 3 X's (on the whiteboard) (usually for speaking Korean, but sometimes also for behavior) they have to write lines (such as the school rules) in their notebooks.
Sigh . . . I hate enforcing any mode of punishment, but I learned a long time ago that most students will not change their behavior unless rules are enforced.
The students whom I have taught for a while know that I am strict but easy-going . . . gum goes into the trash can, if you don't do your homework you get extra work, but if you do a good job you get rewarded in some way.