I stumbled this, and as much as I hate stumbling kana related stuff while stumbling "Japan" I decided to give it a try.
I picked hiragana with everything, First "character" I got was a tenten without any hiragana below it. I got 92/102, which included 1 tenten without character, 1 empty circle, 7 boxes (like the ones you get when you don't have Japanese installed) and 1 misstype. I was hoping it would give me some sort of summary at the end so I'll be able to tell you exactly which characters gave me these troubles, but since I didn't follow up myself and it didn't show I guess I can't do such thing.

It's definitely a good start, but it's a long way from being decent.
And I say that as someone who really hates kana "learning" games and think they're a waste of time.

Decent but, I've seen better

Almost every time I tried to input the CORRECT answer into something like "kiya" it said wrong almost every time. I tried doing it in different ways too and it still told me I was wrong when I typed in the correct answer. I suggest you allow for a little flexibility because you're basically typing out sounds using romaji, which is much more different than doing so in kana.

Also, there was one kana that did not appear for some reason.

I suggest looking over this flash and making sure you didn't miss anything and also to add flexibility when typing in the answer for kana such as "kiya/kya" "hiya/hya" etc. because everyone will have different interpretations on how to sound out the sounds using romaji.

P.S. What is Tenten and Maru?

waa, sugoi desu ne

this helps a bunch, I'd refer my Japanese class to this but my teacher doesn't want the newer people to learn the inproper way to write the characters, (ie: ri, ki etc...) cause the computer connects them, shes just picky xD. But very nice work,, although some of the letters don't show up on the Hiragana for some reason, it might be computer related not you, just pointing it out incase something might be wrong, great job =^^= maybe you could come out with something that is along the lines of basic words etc..? phrases such as " what time is it" etc..

God Bless You

You cannot believe how much this helped me in japanese class.

A few errors I noticed...

I really like this test, it's easy to use and very helpful. I did find a few errors. "Sa" shows up as a blank. "Za" shows up as a blank with a ten ten. Both "Ji" and "Zu" show up as a blank with a square border. Other than that, I say good job. (I haven't gone through all of Katakana yet because I don't know them by heart). I would suggest in a new version a way to interrupt a test with a button to go back to a menu so if you find a test to be too difficult, you don't have to close the window or answer them all. I would also suggest showing what number you are on for each character versus just showing how many you got correct. Maybe a percentage in your grade as well. These are just a few of my suggestions, keep up the great work!