Hi, I am one of Kai's parents. When I try to go to https://classroom.google.com/guar/ODY5MTQ2MzE1NTc1 it tells me that I don't have permission to read that page. Do you need a Google address to issue an invitation? (The address in the From is mine, and house at digitalkingdom.org goes to all the parents.) Best, --Ruth Anne Ladue