Something 'real' is something that actually happened in the world the way it is shown; something 'made up' is something a person imagined or created for a story, game, or joke.+1 more
Things I see on a screen are not automatically true — people make them up sometimes, and checking with a grown-up is a skill, not a sign I don't know.
I can complete a rubric-assessed short oral or written task in which I am shown an age-appropriate piece of digital content, say whether I think it is real or made up, explain my reasoning in a sentence, and name a trusted adult I would ask if I wasn't sure.
