Thanks again for your suggestions, but I'm sorry to say that things are still not working.
I used ipconfig as you suggested on my PC to get the router IP which is 192.168.1.1. Then I added "nameserver 192.168.1.1" to /etc/resolv.conf. And, I rebooted for good measure, and i double checked to make sure the router IP had not changed.
After that, I still have the problem that the RPI3 is not talking to the outside world because eth0 and wlan0 are not working. Adding "nameserver 192.168.1.1" didn't fix that.
So with your Loading Videos instructions, how to I move the downloaded files to "/pi/.kalite/content" on the RPI3? The RPI3 cannot connect to the internet. The "kalite manage retrievecontentpack" command fails because it cannot make a connection.
I suppose that I could download the video files to a USB drive on my PC, then mount the USB Drive on the RPI3 and copy the files in place on the RPI3. Is that what you are suggesting?
Even then though I would still have the problem that the kalite WIFI access point is not working on the RPI3. My whole goal is to load up the Kalite content on an RPI3, then WIFI-connect to a classroom full of 30 students with Android tablets. This doesn't work though because while "kalite" does show up as a WIFI access point, it never connects.
I could try the alternate approach rifatbd suggested for setting up a WIFI access point, above, using the instructions on www.frillig.com , but I'm starting to think I'd be better off waiting for the next release of Kalite to come out to see if some of these problems are fixed.
Maybe I'm being unrealistic, but my hope here was that Kalite would work, out of the box, as described in the Kalite documentation, with no special tuning required.