"Architects of Seamount Ecosystems" is a three part lesson plan that introduces students to the fascinating world of the ecologically critical seamount ecosystems. Students participate in the construction of a Sierpinski Triangle to demonstrate the effect of the branching growth form of deep-sea corals. An award-winning video, "Beneath the Blue" introduces students to key concepts of deep-sea corals. Students conduct online research into the 8 habitat-forming deep-sea corals and prepare a report that addresses 7 key subtopics, including management and conservation issues. The discussion points, web-based research, video, and phenomenon for students to engage in are appropriate for a middle school classroom. Extensive background information and many web resource links, albeit a few are no longer active, are provided for teachers. A suggested extension activity is included.