I think you can go for nice simple shirts and jeans. Along with it you can carry sunglasses as it is considered a style statement. Instead of getting those branded and high price eye wears you can go for wholesale sunglasses. There are many wholesale designer sunglasses,wholesale fashion sunglasses that offer sunglasses at best wholesale price.
giving a girls perspective :)/ wear neat clothes, simple t-shirts, jeans, sneakers and sunglasses. Jacket in case of cold weather. Sunglasses also great accessory to make a look to be cool. as teenagers don't have that much money usually, go for affordable brands, like H&M, Hollister for tee's and jeans. Sunglasses you can find at WearMe Pro, they super affordable.