Hi Jen,
We have them in the library and we don't mind. They are in all common areas (no classrooms) and are helpful in identifying students when they are involved in certain situations. It has come in handy when students try to deface or take something from the library (a keyboard/mouse). There haven't been any complaints and our community seems pretty comfortable/use to cameras in our buildings (they are used in the lower grades/buildings as well). Some feel "safer" and people seem to get over it quickly if they do not like them in the first place. I hope this helps.