How to Build a Terrarium to Watch the Water Cycle

SciShow Kids

This engaging episode of SciShow Kids features host Jessi and her robot rat friend Squeaks demonstrating how to build a terrarium—a self-sustaining miniature garden inside a sealed container. The video bridges the gap between biological needs and earth science by explaining how plants in a closed system survive without being watered regularly. Through clear animations and demonstrations, it illustrates how a closed terrarium creates its own water cycle, mimicking the natural processes found on Earth. The content explores key scientific themes including the water cycle (evaporation, condensation, and precipitation), states of matter (liquid water vs. water vapor), and plant biology. It details specific components required for an ecosystem to thrive, such as soil for nutrients, rocks for drainage, and charcoal for filtration. The video also touches on the longevity of ecosystems, mentioning terrariums that can last for decades without human intervention. For educators, this video is an exceptional resource for hands-on science units in elementary grades. It serves as a perfect launchpad for a classroom project where students construct their own terrariums to observe the water cycle in real-time. By shrinking global concepts like weather patterns and evaporation down to a jar-sized model, it makes abstract Earth science concepts tangible and observable for young learners.