Requesting "DOCX" or "Excel" homeworks is rather common in schools, and you cannot blame them after all, as they don't want to struggle openning documents from their students when they have to skim through hundreds of homeworks during late night.

The easiest way I found to use whatever soft I want is to export everything in PDF, or any common format readable by the Office suite.
You can also use Google docs when you're screwed, as they're platform agnostic.

For your reports there is always LaTeX which can be exported to PS/PDF. But markdown would be the simplest choice (learning curve is nearly flat). You can then export them to HTML, then PDF with your favorite browser, or to PDF directly with pandoc(1) (it will be your best friend for document conversion!).

For spreadsheets, I've always used CSV (doesn't support calculations though, I must say I never encountered this use case, and I'm glad I didn't!). I'm not expert there, so I guess google spreadsheet is your best choice.

And then presentations... At the end of my grade, all teachers requested powerpoints. I decided to screw this, and went with impress.js[0]. They were all impressed (hehe) and I got a pretty good note for originality!
It takes some work though, so for quick prez, sent(1) would indeed be best.
In case your teacher doesn't want to compile it from source, you can still screenshot all slides in fullscreen and make a PDF out of it.

There's always a solution, even if it might involve more work for you ;)

[0] https://impress.github.io/impress.js