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I remember a TV show from the 90s in which a boy from our Earth somehow ends up on a parallel Earth in a pre-industrial society. IIRC, it's a counter-Earth on the other side of the sun.
The part I remember most distinctly is that he meets a girl of a similar age, and he tried to explain a heliocentric solar system to her by rotating around her. The villagers mistake this as some kind of courtship dance and get upset.
I have a vague recollection of it being maybe a BBC or CBC production, but I'm not certain.