Help me with whiteing my teeth ?

Ok , im 15 years old & my soft-more year at high school is coming in september .. I have braces and right above them is kinda yellow yes they are "grown up teeth" , but i still wanna make them as white as possible . I brush 2 times a day , morning & night . I was wondering if i could use "Crest whitening strips" PLEASE HELP `! . thanksss (: