Just out of interest?
And before I get roasted alive, I do know that it doesn't matter and we can get them out of the library. But I'm starting to have issues with the lack of initiative and, well, any kind of trying at DD's school. I think the infrequency of book changing is one symptom of this, but want to make sure my expectations are not unreasonable.
To give you an idea, they are supposed to be changed every week, but our record so far is 2.5 weeks.