Your sister is starting 9th drake next year, what step would you recommend she take first?

Make sure she has supplies ready, pen paper, pencils, books, ... ect. she will need to keep her stuff organized, make sure you have plenty of extra time in between classes in case you for get something, take lecture notes, correct paper if you can, even if you passed them, try not to miss school, practice good study and test taking skills.

the first step is to find a good set where you can here the teacher, siting in the back of the room is proven to get lower grades and less knowledge then being in the front.