[Sinestra]

Im not sure why but im having a hard time remembering Katakana. I learned Hiragana in about 2 weeks and im even picking up Kanji decently. But for some reason i cant seem to retain Katakana even though i study everyday with flash cards and even a flash card app on my iphone. I receive homework constantly from my Japanese teacher with Katakana and i still have to look up certain characters.

Has anyone experienced this problem and if so how did you over come it?

thanks guys