Earlier you told me it was gadget you deceitful owl.
i have reported it
Or how about gadget or apparatus?
Yeah, I was thinking that the most general sense of the word "Gerät" would be "appartus", though it might be a little more formal than, say, "tool."
Surely 'It is not that device." is technically also right, isn't it?
Yes. I just put 'It's not that device' and it was accepted.
Isnt equipment also a valid translation of "das Gerät"
No idea if Duolingo accepts those here, but the answer to both of your questions, neil and radami, is yes.
Is there a way for this not to sound so weird? Could "machine" or "appliance" work? "Device" seems like an unusual word for a chapter on simple household objects.
The leo dictionary has machine and equipment as also being translations. Back when I was taking German in high school it was always spot on - so maybe not as definitive as a German speaker but I believe it. dict.leo.org if you didn't know about it.