Clothing for high school?

so I'm going to be a high school freshman next year and this summer I'm trying to get some better clothing besides just tshirts. my town doesn't have very many stores (old navy, jc penneys, rue 21, vanity, maurices) but I'm going to a bigger town soon (two weeks) that has all the popular clothing. so just what do I need for a good wardrobe for high school?