Sponges are actually animals. They are the first evolved animals, followed by jellyfish. All other animals evolved from sponges. Sponges are the only group of animals that can migrate some of their cells and give them a new function. Some are carnivorous, but most aren't.
You know you feel old when one of the first non-CN shows you remember was the German series Twipsy. This doesn't strike a chord with Americans, though. I remember being 4 and being enthralled by the computer graphics of the cyberspace setting.