Library Assistant Question:

This question also comes down to personal preference, but here's what I do.
I put behavior procedures in place starting on day one. You can find all my library behavior information when you sign up for my free library lesson plans. You can find all the resources that go with the lesson plans here. You can also check out my post about behavior management in the library and my podcast about how class dojo is Changing My Library. I think the main concern with this question is that you are able to handle your own classroom issues, with the exception of extreme cases.