Yes, ensure that if you have two APs close to each other, that they aren't on the same channel. So for example if you if you have two classrooms back to back, ensure that they aren't both on channel 36, but maybe 36 and 44. I've seen symptoms like you mentioned where the Macbook would be associated to wireless, but no internet.
Have you seen this article for channel planning?
https://gtacknowledge.extremenetworks.com/articles/How_To/How-to-create-a-5GHz-WiFi-Channel-Plan/?l=...
As for the Apple commands, the one I mentioned will give some good output based on where the Macbook client is sitting. This command will show what AP the Macbook is associated to and information like signal strength: /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport /usr/sbin/airport -I