Every now and then I come on a thread like this and say 'don't be so silly, of course teenagers should be reading and discussing that, how else will they ever learn or express anything?'.
This time though.... Ian McEwan's early work is really dark and disturbing. I would not like an 11yo to read The Comfort of Strangers or to have to try to explain that to them. A Child in Time wouldn't make any sense and Cement Garden is grim.
All fine for late teens and I wouldn't be shocked about a well read 13yo reading most things really but, developmentally, 11 is very different from 13 (and that's writing from my experience as a girl, who are on average more mature at 13 I think).
They should stick to Lord of the Flies if they want something provoking. I'm serious, at least there's no incestuous or masochistic sex!
So yes, lazy homework topic and, while writing a very basic biography of McEwan (dates, education, some titles, prizes), would seem harmless, if not very informative in itself, I would raise with the teacher the issue of what anyone compiling a list of his books would come across.