I'm applying to UIC gppa...?

...for letters of recommendation it says that 3 are required. Can you send more then 3 or will they only look at three of them and disregard the rest? Because I wanted to ask for one at the hospital where I volunteer, but two that I have from school teachers are ones I really want too because they will be more focused on academics. And I have one other teacher who I've known since freshman year because I have her as a badminton coach. So I really want her to do one too.