How can I prepare for becoming an elementary school teacher while I'm in High School?

It feels like all of my friends are preparing for their future career. My friend who wants to be a fashion designer is taking sewing classes, internships etc. Another friends who wishes to become a scientist of some sort is taking all of these science classes and also special programs and things. I want to become an elementary school teacher and I want to know what types of things I can do to prepare for it, and possibly put on my college applications? Thanks.