Pitching in a little late.
Mine was a TA for French 2/3 in her Junior year and now helping out her Precalc teacher and her AP CS teacher unofficially as a TA (though that is not captured in the application). Being a TA in French class enabled her to bag a 5 in her AP French and she made some lifelong friends as well. It also created a bond with her French teacher who’s one of her recommenders. Got into a T10 in EA if that would help you.