Ok, something that is a little frustrating here:
The training consistently presents です as simply expressing politeness. To be honest, every time I see that, I have to fight the urge to ask for a refund.
です is “to be.”
Is, was, am, will be, is in, or at: it means all of these things depending on the context and conjugation.
Presenting it as being polite will lead not only to confusion as tho when to use it, but also inaccurate translations. 
I’m working through Japanese 1 as a stepping stone, because I know I am not quite ready for Japanese 2, but when I run into something that is like super basic expressed in a way that is not useful or even accurate, it’s jarring.
The training session is basically done for the day as soon as I hit that question, because it throws me totally off track.
I submitted this through the feedback form as well, and the bot told me to post to the forum. Maybe I’m just missing something?
(I just submitted the feedback a few minutes ago, so getting a message from a bot isn’t a bad thing. 
If a human sees the message, they may very well say the same thing)