Here’s the thing: if you delete your whole Google account, any Google Classroom you created as a teacher disappears too. That’s like burning a book you loaned to the library—you’re the hero and villain of the story. Students will lose access, and your old assignments will vanish into the void.
If you’re a student just leaving a class, don’t worry. Your teacher will just see a notification that "Student X has left." They probably won’t cry—they’ve got a hundred other assignments to grade. Unless you were their favorite. In that case, send them a nice email first. It’s the digital equivalent of baking them a farewell cake.