Why Do Sunflowers Follow the Sun?

Description:  This is an excellent phenomenon that can be used in many different units. According to researchers only young sunflowers will follow the Sun. These flowers are following a natural circadian rhythm to receive the most light for photosynthesis. However when they mature the flowers will mainly face east. The reason for this is fairly simple, bees like warm flowers, and the flowers facing the east are the warmest.

Web Resources:  The Mystery Of Why Sunflowers Turn To Follow The Sun — Solved - NPR, Helianthus - Wikipedia

Biosphere 2

Description:  Biosphere 2 was created in the 1990's to model all the elements of Biosphere 1 (The Earth). Plants in the biosphere produced oxygen and food for the inhabitants. The carbon dioxide released during respiration was taken in by the plants cycling the matter with energy from the Sun. In this experiment oxygen levels steadily fell to dangerous levels and oxygen eventually had to be added to the biosphere. This large-scale phenomenon continues to be owned and run by the University of Arizona. The mystery of missing oxygen could be used as a phenomenon in a unit on matter cycling and energy flow. Students can even create biospheres of their own and monitor life over time.

Warning: This video contains strong language (11:06) and is not appropriate for younger viewers. Please use teacher discretion when showing segments of this video directly to children.

Web Resource:  Biosphere 2 - Wikipedia

12 Years in a Sealed Ecosphere

Description:  The Ecosphere in this video has been sealed in a glass container for 12 years. No air or food was able to enter or leave the Ecosphere during this entire time yet the shrimp are all still alive. This phenomenon can be used in the elementary science classroom to introduce plant and animal needs. It can be used in middle and high school to address matter cycling and energy flow.

Web Resources: Ecosphere (aquarium) on Wikipedia, Ecospheres