@tsarstepan,
You have them.
Over here there's a complete change over the summer, when the kids come back they often have new teachers and in some cases ne subjects.
Trying to get kids to read over the Summer is a no brainer, you can make suggestions, and some kids do read, but homework? Forget it.
They won't do it because there's a good chance they'll have a different teacher on return, and a new teacher isn't going to want to get off on a bad foot by chasing up historical homework.
As it is kid's performance drops over the Summer, and it usually takes until October to get them back up to scratch.
I used to tell the kids to read something they liked, if it was comics or magazines that's something, it may not be Thomas Hardy, (who I loathe btw,) but at least it's reading.
I live in Hardy's Wessex although at the moment everyone is banging on about Jane Austen, some anniversary going on, and she's on the tenner.