You also need to download basically anything that Yoko Kanno has done. She's composed the music for a lot of fucking phenomenal OPs, such as this one... http://www.youtube.com/watch?v=Fvb12RxGTcg
That was right when the song would have started so you probably didn't hear it. Elementary kids might make up words, but it will never sound as convincing or as fucking beautiful as this:
I realized it was clearly a spoiler, but I needed something that would grab you by the balls immediately so you'd want to watch it. How much of the video did you watch?
And I hope you know who Yoko Kanno is. Her soundtrack for cowboy bebop is considered one of her greatest works... and she's known for causing mass quantities of erections with her soundtracks. As a little example of her brilliance, if you heard any of the song in that video... can you guess what language it is? Well, it's a trick question, because Kanno made up the lyrics. Yes, as in it's a language she created specifically for that song.
The second season of zero is marvelous. It even has what should have been the proper ending... then they went and made a third season. I thought the 2nd season was better than the first.
I'm... assuming... you haven't seen Cowboy Bebop, otherwise you'd know Spike is a fuckin man.
I have no idea how anything I said reminded you to watch zero no tsukaima, but regardless, it's a great series so you should be watching it. The first two seasons are awesome. The third season... mehhh. It's worth watching for more Louise fanservice.