I'd never really heard of My Life as a Teenage Robot, but it caught my eye stumbling across channels one day. I stayed tuned as the episodes kept rolling, and it struck me - this show is really good!
The plot's pretty simple - mad scientist Dr. Wakeman programmed XJ-9 to defend the Earth, but after being discovered by her human neighbors, Brad and Tuck, "Jenny" decides she'd much rather fit in with humans - but has to get over some of the social hurdles of being a 6 foot-tall, steel-plated, heavily armed war machine.
The show does really well with its premise. Even at their extremes, the characters are all likable, and have some great voice talent to back them up. The pacing is very relaxed, without a lot of the exhausting hyperactivity you see in a lot of newer shows.
The animation has a very traditional style. The characters are a mix of '60s Hanna-Barbera, Astro Boy, and Felix the Cat. The backgrounds look hand-painted with abstract Art Deco and Populuxe designs. And despite being a scifi-themed show, there's none of the conspicuous CGI common to classics Futurama and Invader Zim.
I was just getting started with this show when I found out it had been canceled for a couple of years, which is a shame because it still seemed to have a lot of energy in it. I'd call it an underrated classic for fans of scifi and animation, and probably good enough for Nick's intended audience, too.