Is this worth making a move or no?

It's not worth making the move. You shouldn't flirt with her if you're not planning to be her boyfriend- that'll just confuse her. A side from that, she's only going to be going into middle school, and you're starting high school? That's kind of bad. If you want to make a move on her, to be her boyfriend, wait until she's dated a few guys her own age. Just because you can't be her boyfriend, doesn't mean you can't point her in the right direction, either! If you think these guys aren't right for her, be her big brother & tell her that you think she's to good for them. This will also help you build up trust with her, so if you want to date her in the future, it'll be better for your relationship.