Summary Use real animals and plants, and molecule models, to show how living things exchange carbon with the atmosphere. Science content Biology: Food Webs, Ecosystems, Biomes (3, 4) Earth/Space: Sustainable practices, Interconnectedness (2, 5, 7) Activities in this lesson Worms: close observation Worms: indoor compost bin Molecular modelling of respiration and photosynthesis Plant growth in a sealed jar Materials Materials in the activities Procedure Introduction to Carbon cycle lesson series for older grades: The carbon cycle circulates carbon between animals, plants, the air, soil and rocks. Introduction to Carbon cycle lesson series for younger grades: Chemistry is one way that Earth's living things, its water, air and rocks are connected. This lesson focuses on how animals and plants are connected to the air. Do a worm observation, then put the worms in a classroom worm bin. Worms, just like us, need air, and the oxygen in it. as well as food, for energy. Use molecular models to show how the worms use food and oxygen (called respiration). Plants do the opposite to us animals. They take carbon dioxide from the air and make food and oxygen with it (called photosynthesis). Plant bean seeds in a jar, which will use carbon dioxide in the har, and the sun's energy, to make sugar and build a plant. Leave the jar closed and keep in the classroom for a week. Optionally show the opposite chemical reaction (photosynthesis) combining CO2 and water to make sugar. Notes Lesson 1 of 6 of a series on the Carbon Cycle. Good image of the whole carbon cycle at https://www.britannica.com/science/carbon-cycle Grades taught Gr 2 Gr 3 Gr 5 Gr 6