Butterflies & Caterpillars

Children will explore the life cycle of a butterfly.


Lesson Objective

Children will learn about the life cycle of a butterfly as it grows from caterpillar to butterfly.


What You'll Need

  • Butterfly cage – available at discount stores, or use a 10-gallon aquarium with a mesh lid
  • Monarch caterpillars – 5 – white, yellow, and black stripes (see Lesson Tips)
  • Dirt – 2“ in cage
  • Grass with roots
  • Milkweed
  • Branch of milkweed plant (where caterpillars and their eggs are found)
  • Magnifying glasses – 1 per child

What To Do

Note: This lesson will take 2–3 weeks to complete. Try using monarch caterpillars (see Lesson Tips) because they will emerge from their chrysalis in only 14 days. You will need a daily supply of fresh milkweed for the caterpillar, enough for approximately 14 days.

  1. Display the caterpillar(s), and activate children’s background knowledge about caterpillars and butterflies (see Did You Know?).
  2. Tell the children they will be exploring the life cycle of a butterfly as it emerges from being a caterpillar to a beautiful butterfly. Make the children aware that once the butterflies have their wings, they will be released.
  3. Place dirt in bottom of the aquarium 2" deep. Plant the grass in the dirt. If you are using a butterfly cage, you can omit this step.
  4. Place caterpillar(s) attached to the branch of the milkweed plant where you found them in the cage/aquarium. Add another branch with leaves (replace with fresh leaves daily). Place the cage outside in a shady area. Lightly mist it once per day to maintain humidity.
  5. Have the children observe the caterpillar daily, add fresh milkweed, remove old leaves and excrement, and document any changes.
  6. Once the chrysalis has formed, have the children make predictions and track on a calendar the time it takes for the butterfly to emerge.
  7. When the butterfly emerges, its wings will be very wet, and it will not be able to fly until they are dry (3–4 hours).
  8. Once the butterfly’s wings are dry, release it to the outdoors.

Guiding Student Inquiry

  • Explain what happened to the milkweed leaves.
  • Why do we need to replace the leaves every day?
  • Tell me what the caterpillar is doing.
  • Describe how the caterpillar became a butterfly.

Explore, Extend & Integrate

  • Search for other caterpillars outside. Have the children compare their colors with the monarch caterpillars; discuss what color butterflies might emerge from these caterpillars.
  • Look on the underside of leaves for butterfly eggs. Discuss why the butterfly would lay its eggs on a leaf.
  • Look at pictures of butterflies, and discuss how the wings are identical (this is called symmetry). Make butterflies by tracing a pattern on folded construction paper. Place 2 or 3 large drops of paint on one side of the paper, fold it in half, and spread the paint by pressing on the folded paper. Unfold the paper to reveal symmetry on both sides of the butterfly wings.
  • You can plant milkweed seeds outside early in the spring. By late summer, you will have your own supply of milkweed for your caterpillars.

Check for Children’s Understanding

  • Could children describe how the caterpillar became a butterfly?
  • Could children explain that the chrysalis was made by the caterpillar?
  • Could children explain the stages in a butterfly life cycle?


Did You Know?

The life cycle of a butterfly takes place in four stages: egg, larva, pupa, and adult. The whole process takes about 30 days. Butterfly eggs are usually found on the underside of a plant leaf; monarch butterfly eggs are tiny yellowish-orange, oval shaped balls found on the underside of a milkweed plant leaf. Once the egg hatches, a tiny caterpillar emerges. The caterpillar is a butterfly larva. Caterpillars eat quite a lot and grow quickly. When the caterpillar is finished growing, it forms itself into a pupa, also called a chrysalis. Once inside the chrysalis, the caterpillar will undergo a transformation called metamorphosis, and a beautiful butterfly will emerge.

Butterflies lay their eggs on the underside of plant leaves they like to eat. When the tiny caterpillars hatch, they will need to eat and eat. Each type of caterpillar only likes to eat certain types of plants. For example, monarch butterflies eat only milkweed. Adult butterflies have a very short lifespan and need to be released to the wild as soon as they can fly—to lay their eggs—and the cycle begins again.

Vocabulary: Child-Friendly Definitions

  • butterfly – a flying insect with wings that often have bright colors.
  • caterpillar – the larva, or middle life stage of a butterfly.
  • life cycle – the sequence of changes that a living thing goes through as it grows and develops.
  • larva – an insect after it hatches from an egg and before it changes into its adult form.
  • pupa – an insect in a middle stage of its development, after it is a larva.
  • metamorphosis – the changes in form of some living things as they grow.

Lesson Tips

  • Butterfly kits, including caterpillars, are available rather inexpensively at discount stores and online.
  • Milkweed sap (white, milky substance) that comes from cutting the stalk can irritate skin and eyes. Be certain to thoroughly wash hands that have come in contact with the sap with plenty of soap.
  • Locate an area along a creek or farmer’s field to harvest a supply of milkweed to feed the caterpillars, or order milkweed online. Milkweed can be kept in the refrigerator. Make a fresh cut across the bottom of the plant and place it in a container of water; put this in the refrigerator. It will stay fresh for several days.


  • The Very Hungry Caterpillar by Eric Carle
  • From Caterpillar to Butterfly by Deborah Heiligman
  • National Geographic Readers: Caterpillar to Butterfly by Laura Marsh
  • Ten Little Caterpillars by Bill Martin Jr.

Home School Resources

Home educators: use these printable lesson PDFs to teach this lesson to your home schoolers. They're available in English and Spanish.

Home/School Connections

Las Conexiones a la Casa

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Content Provided By

Common Core State Standards Initiative – These lessons are aligned with the Common Core State Standards ("CCSS"). The CCSS provide a consistent, clear understanding of the concepts and skills children are expected to learn and guide teachers to provide their students with opportunities to gain these important skills and foundational knowledge [1]. Visit the CCSS