This is a short 5 lesson Stem unit on ecosystems and environmental engineering. It starts by building students background knowledge on technology and engineering. It then moves into learning about what an ecosystem is, and what different parts make up an ecosystem. With all this background knowledge it then moves into learning about beavers and how they are ecological engineers. They use their adaptations to engineer their own ecosystems. There are lots of art based activities to allow students more ways of expressing their understanding.