How much are you actually distracting her in school? If you're in class with her, I'd recommend still talking with her, but instead of talking about a bunch of little things, focus on whatever you're supposed to be doing in class (and once that's done, talking about other stuff), or if she's working on something that you aren't, have her focus on that. Being near her and being available to help her if she needs it will make a big difference to her. I'd recommend doing that if you really want to get in a relationship with her. The key here is balance. You don't want to lose sight of whatever you're done, but at the same time, you don't want to get so absorbed in it that you forget about each other. So control yourself some, but at the same time, still try to have a little fun. And of course, if whatever you have pent up still isn't being satisfied, waiting and talking with her after school to let all that out is still an option. Just make sure that she's getting enough time and concentration to finish what she needs to finish.