<p>I think you have a good chance at all of these schools 
just try to take more AP classes, what were your scores on the 2 AP exams you already took?
Also, make sure you want to go to these schools because you actually like them, not just because they’re ivies. Columbia has a pretty strict Core curriculum, while Brown has a more ‘open’ type course selection. Penn is pretty pre-professional focused (ex finance, wharton, nursing schools), and some people say Harvard doesn’t focus much on their undergrads. These schools are actually very different, so do some research and don’t apply to all of them just because you want the ivy brand-name.</p>