HELPFUL WEBSITE FOR HIRAGANA AND KATAKANA MEMORIZATION!!!
When I took Japanese in school I used this website to study my hiragana/katakana...
This website lets you select certain characters then tests you on them. You can go from doing あ,い,う,え, and お, to all 46 of them. I recommend that before you start learning vocabulary and grammar you should commit all hiragana and katakana to memory. Trust me, if you are fluent in identifying all of these characters then learning Japanese will go much smoother.
I learned Kana (in only a few weeks) from these courses:
Up to you which works for you.
Also the below links could be very useful to learn, practice and memorise Hiragana and Katakana..
there are also listening quizzes: