the shadow of "kage bunshin' isn't the same shadow in 'kage mane"...
the shadow clone is merely a replication technique with a cool name, it has nothing to do with shadows, while the Nara family actually utilizes their shadows to catch thier enemies... is the diffrence clear to you?

they can't all know super cool jutsus, becuase there aren't that many jutsus to know... it's not YYH or some other super-powers anime, where everyone has thier "ougie" movement... the charecters in Naruto will probably learn a couple of new Jutsus until the series end..

oh, and just for a quick note, it's only team seven who doesn't have jutsu, the rest of the teams know quite a bit jutsus (ino had the hair thing, and both Neji and Tenten know the basic's of the lotus)... the reason? Kakashi sucks as a teacher.