Life cycles describe the process by which living things change from life to death.
Teaching life cycles to your second-grade class gives you the opportunity to bring your classroom alive -- literally. The most effective way to teach your students about life cycles is to allow them to observe the life cycles in real time. Books, charts and physical activities will help reinforce students' understanding of their observations.
Plants
Beans can be grown without soil, which makes it easier for students to watch their growth.
The life cycle of a plant can be taught by having students plant their own bean seeds in clear, plastic cups. A moist paper towel should be placed in the cup and the bean should be visible. Every day or two, the students should draw pictures of the plant in booklets and describe the differences they see. The students can act out the progression by curling up as "seeds" and growing slowly until they fully stretch out their arms and become "flowers."
Insects
After your butterflies emerge from their chrysalises, give them fresh flowers.
There are two different types of insect life cycles: three-stage and four-stage. Discuss different types of insects with the students. Insects such as ants and crickets pass through three stages: egg, nymph and adult. Insects such as butterflies and ladybugs pass through four stages: egg, larvae, pupa and adult. Posters showing each stage should be used. You can also order live insects in their egg, nymph or larvae stage so that the students can observe them as they go through their metamorphoses.
Frogs
Tadpoles transform into frogs slowly, allowing the progression to be easily observed.
Discuss the life cycle of frogs with students -- from egg to tadpole to frog, explaining how the tail shortens and the legs grow. Create a poster, with a picture of each step attached to the poster with tape or Velcro. The students can take turns putting the pictures in order. Raising tadpoles in the classroom allows students to observe the transformation. A 20- to 30-gallon aquarium is the perfect size for raising tadpoles. As the students observe the progress, they can record their findings.
Birds
Caring for chick eggs takes diligence, but is well worth the effort.
The life cycle of birds can be taught while raising chickens or ducks in the classroom. Read a book about hatching eggs. Some examples are "Horton Hatches an Egg" by Dr. Seuss, "Egg to Chick" by Millicent E. Selsam and "The Chick that Wouldn't Hatch" by Claire Daniel. Discuss how the incubator does the same job as the hen. The students can observe the eggs daily for signs of hatching.
Tags: students observe, life cycle, life cycles, different types, Insects such