I documented my findings with logging into Seesaw via Google a couple of weeks ago… here is my update from that post:

After contacting Seesaw, it appears that many of our student accounts had no passwords. Therefore, the students were unable to use the Email option. Normally, a user could have fixed the issue themselves by clicking on the “forgot password” link; however, our student emails are not active and would not receive the necessary reset link. Therefore, we had to use the CSV roster import feature to do a mass updating of the passwords. And it worked!

Now, we are able to use the Email option which does a “clean” sign out of Seesaw… In other words, no more extra steps of having to log out of Google as well on our shared devices.