@futurebird
Remember when Replit let you run a web IDE for free? Pepperidge Farm remembers.
If you want/need to use another browser-based IDE, then CodeSkulptor3 might be your best bet, although programs with multiple files seem... difficult. Not impossible though. Trinket recommends Pickcode in their announcement. I haven't tried it.
If an Android app would be better, then apps like Micro REPL, Acode, or Squircle CE are all open source and at least let you edit python code, although for the latter two I'm not certain they're able to run it (although they probably still can). Pydroid seems more powerful, but I'm unsure how much they'll push their paid features.
I think Chromebooks have a Linux layer you can enable without changing the user experience otherwise, which would let you use the normal programs. But I'm not sure you could convince IT to enable it, or if performance would be good enough under it.
Since Trinket is going to open source their code anyway according to their announcement (and they're shutting down in early August), most likely someone in the community (possibly you) will be hosting a version by the time the next school year starts. They might let you have the necessary files early if you ask. The worst they can say is no.