What three methods do echinoderms use to get food?

Echinoderms employ several methods to obtain food, primarily through filter feeding, scavenging, and predation. Many species, like sea stars, use their tube feet to pry open bivalve shells and then extend their stomachs into the prey to digest it externally. Others, such as sea urchins, graze on algae and other organic material from surfaces. Additionally, some echinoderms, like sea cucumbers, filter feed by sifting through sediment to extract nutrients.