Well, in order to get to the friend level you'll need to get more points on her heart meter. After you get so many, you'll probably be able to unlock the events you want.

For instance, is she on the student council? Maybe you can ask to help her out every now and then. After a while her heart meter will probably go up.

But be careful to choose the right things to say. Right responses can increase her heart meter, but some wrong responses can dramatically decrease it.