My high school’s instruction in English, when it came to Greek tragœdy such as Sophocles’s Antigone, gestured at Aristotle’s unities of place and time; but these seemed arbitrary things to commit to memory. Not until I had graduated from university, and was taking a class about the history of rhetorical theory, did I actually read Aristotle’s Poetics and understand what he was on about. I wish we had been set to read Aristotle in high school to understand literature and rhetoric. Richard Carroll gives a review of the Poetics at Thermidor Magazine. Unlike Mr Carroll, who recommends the Loeb version, I might instead recommend the translation of Rhys Roberts and Ingram Bywater, which is bound together with Aristotle’s Rhetoric; which to choose depends on what you need.
If you haven’t read Mr Carroll’s review, do go and allow him to persuade you to read Aristotle’s Poetics. I don’t think you’ll regret it.