2. Refers to a group or collection of pathetically stupid kids, where the 's' in kids (or kid's) is dropped and replaced with 'z' to denote their stupid nature.
3. Kids that act like retards usually to get attention who inadvertently embarrass those with real mental disabilities.
4. A group of stupid kids that ascend beyond the levels of average stupid kids.
<Jimmy>: hey wtf is that guy doing to that stop sign?
<Timmy>: that my friend would be a stupid kid trying to attempt an ollie, with a dislodged stop sign... oh look he's got his lighter out, guess it's not a challenge unless it's on fire too. Dear lord, his friends are video taping it.
<Jimmy>: lol, stupid kidz!!
<Stupid Kid>: Screw it, this algebra blows. Hey dude, wanna leave class and play hacky sac?
<Dude>: No way man, I'm not gonna skip class to toss around some frikken bean-bag!
<Stupid Kid>: You suck! *smacks him with hacky sac*
<Dude>: aww fuck! wth!?! *throws said sac back in retaliation*
<Stupid Kidz Stupid Friend>: c'mon bro, let's get wasted... we don't need this turd. *smacks dude with his own sac*
<Dude>: *throws the second stupid kidz hacky sac out the window* Fetch bitch!
<Stupid Kidz>: *flips off the dude and make their way out the window*
<Teacher>: *hears dude* That will be detention for you mister!
<Dude>: asswipes! damn those stupid kidz!