Rugrats and Looney Tunes are top-tier old school. Although you could probably argue about either one of them actually being old school. But they are to me.
I'm a fan of Flapjack and Adventure Time, but not so much Chowder. It'll do in a pinch.
I think if I watched Hey Arnold again today, I'd like it a lot more than when I was younger. And of course, this thread would be awful if there was no mention of Invader Zim.
LCN's favorite cartoons? ANYONE EVEN WATCH THEM ANYMORE BESIDES WALRUS AND ME?
I was going to mention Ed, Edd, n' Eddy, actually. That and Looney Tunes are probably my favorite Cartoon Network toons, unless I'm forgetting even more. And I loved Avatar.
I actually don't like Tom and Jerry that much, but that's mostly because I got angry Cartoon Network still shows it and not Looney Tunes.