Thanks, Aly!
I appreciate all the thought and effort you and everyone else has put into my query!
If I don't forget, - which I sometimes do, once a problem is resolved - I'll post about our choice and the results.
I'm leaning toward toktumi, but we may not even need that with Verizon's Nationwide plus Canada and texting.
It will be strange to be able to call the kids directly when they are at school, we have been texting and using Skype for conversations.