Putting aside The Revolting Slob (which still does serve an educational purpose), Crashbox is everything kids' shows should still be but aren't anymore. Inventive, artistic, funny, and not dumbed-down. You're not going to hear any characters on Crashbox shrieking the same word over and over and over....and over and over and over....for an entire 20 minutes and calling that "education". Watching Crashbox, I'm reminded strongly of the shows my siblings and I used to watch on PBS in the 70's, especially Canadian PBS.
Here's a less yuck-inducing clip from Crashbox: the awesome Radio Scramble.
Also! The Riddle-Snake had a good one on one of the episodes we watched this morning:
Where was King Solomon's Temple?
On his forehead!