So they confirmed it. I knew that the bowl cut girl in the yellow dress was Noah's twin :)
The few shots she is in are very interesting, but all the school scenes are, they hid so many clues.
Here we see "female Will", El, Will and the "Henry Ford boy", who also could play his twin.
In the shot we also see the name Ruby, which means red, a red haired girl who resembles Robin and wears a hat similar to Robin's Scoop Ahoy's one (there's red in Will's and El's t-shirts too). And the name of Ruby Bridges' teacher was Barbara Henry.
Then, this shot. Every single movement is intentional, it's almost a dance. For a moment it looks like Will is "gone" and only El is there (exists?)
And then El is gone, we only see Will and "female Will", and Will looks at his left wrist, the tattoo wrist. Another intentional detail.
(also, Will is blocked by a black visual aid, El by a white shirt. Black and white, like chess pieces)
Anyway, the Duffers are twins, so maybe they just wanted Noah to have his twin in the show for a little scene.
But like I said, they hid so many clues in these scenes, so maybe it wasn't just a fun cameo. For example, behind Will and his twin there's a girl with a black and white shirt, whose pattern looks a like a strand of DNA, and we also see the name of the father of microbiology (Anton Leeuwenhoek -> Dimitri's last name is Antonov)
Another school project is about John D. Rockefeller, who had two siblings that were fraternal twins. We see his name when Jake and Angela are in the shot
And they're also in the shot with the Wright Bros visual aid behind them.
