Hey, I don't see much for middle regressors on here, especially for older kids >.<
I slide from 12-14, and here's some things I like to do in middle space ^-^
Sailor moon (the original series... it's just better I'm sorry)
Madoka Magica (spooky... watch with caution!)
Fnaf/bendy/any mid-2010's nostalgia game let's plays (not a tv show, I know, but they're so underrated...)
Friendship is Witchcraft- a fun and edgy My Little Pony parody. You can watch all the episodes on youtube! Plus, they have some pretty banger songs.
any collection of Foxtrot comics, they're just really good <3
What Would Emma Do by Eileen Cook (features religious themes, mostly about questioning the things you've been brought up with)
Ghoul Next Door- one of the poison apple books from scholastic book fairs. I also recommend Curiosity Killed The Cat
School Spirit: Suddenly Supernatural by Elizabeth Kimmel
Sticker making! All you need is some scissors, paper, and tape
baking- I like making cookies from scratch. Also maybe just me, but I like doing the dishes while the cookies cool. Plus, as a middle, you can probably do that on your own ^-^
Picrews! I LOVED making random OCs when I was 14, and dress up games are just that, but quicker
Hanging out at a mall or cool shopping center- I never got to do this as a kid, so I'm super glad I can now <3
Writing fanfic! I like to try to make mine as "cringe" as possible, just because it's fun. Write all the weird self-insert stuff you want, it's a blast
On the topic of writing: keeping a roleplay journal. (not as weird as it sounds, I swear) I have a sparkly notebook that I journal in about a make-believe middle school I go to. There's drama, you make pretend school notes, plus obv more OCs... it's something that really helps me get into the headspace and relax. Don't knock it till you try it!