I am a 12th grade in a scientific school type and this year I want to try to go to MIT.
You only have 2 minutes to showcase all your work so I think it would be easier to put everything in 1 video. Plus you can only submit (1) PDF for supporting technical documentation/specs. not multiple PDFs so it might be better to have all your project specs and docs. on a PDF portfolio. This way if you have an introduction to yourself/your projects you can perhaps use the first 10-20 seconds to explain what they are seeing.
Good luck.
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