I have about 20 students at my school using MacbookAir computers. I am having difficulty keeping them connected to my WiFi network. They continue to bounce around, trying other WiFi connections. Some of the SSIDs that they are trying to connect to are no longer valid but the Mac continues to look for them. As a result my users are continually getting disconnected.
My access point is an Engenius EWS360AP. One person suggested turning off the 2g radio and only letting them connect to the 5g. I have been adjusting the WiFi connection on each computer to put the desired SSID at the top of the list and then telling it to ask before joining any other network. This seems to help but it is only a stop-gap measure.