From the simplest sponges to the chordates (which include us), animals are grouped into phyla by their body plan. The arthropods are by far the largest. ▶ Play to meet each phylum.
A key sorting feature is symmetry: none (a sponge), radial (a jellyfish — identical all the way round) or bilateral (a left side that mirrors the right — most animals, including you). ▶ Play.