Hey,
I enabled it over 2 summer ago and had to turn it off. I am not sure where geographically you are in the USA but we have major issues.
Without a policy or governance/compliance program, you are going to run into several things like teachers traveling during the summer internationally, students who travel during the summer, even during the school year, internationally, and possible contractors who are international (e.g. we use Google as are source of auth but turn off all the other services by OU).
If you figure that out the next hurdle is what you are experiencing. When I had it on, I had people literally standing next to me, within my building, who were blocked by geographical restrictions. Their ISP was handling out IPv6 addresses (cell phone) that were originating the IP addresses from upper New York. I had to believe that the close proximity to Canada was the issue. In addition, I had teachers within the town, the state, and the continental USA who were getting blocked. I started to have to whitelist all our islands (not just Hawaii), Canada, and Mexico, and then without a policy (referring to above) Italy, Germany, UK, and even China (had a student there).
Now I hope some how they have smarter intelligence (oxymoron I know) for when you turn it on or are trying it. Maybe geographically in the USA are more central to the country then I am but if they are going off only originating IP addresses, not announcing, you could still be in a pickle and huge inconvenience.
We geo block at our firewall for inbound connections to our sites, use the whitelist IP allow for Google Admin Console, but have to look the other way on the geo feature of the context aware until they have a way to truly allow and only allow the USA.
Mike