Life Cycles for Kids: Butterfly, Frog, Plant and Chicken Compared

Life cycles for kids are easiest to understand side by side: a butterfly, a frog, a bean plant and a chicken all start from an egg or seed, grow, become adults and make the next generation, but they change in very different ways and at very different speeds. This guide compares the four stage by stage, with typical durations from museum, wildlife-charity and university sources, plus age guidance and activities.

Every timing below is a typical range, not a rule: species vary, and warm weather speeds most stages up while cold slows them down. For printable sequencing and labeling sheets to use alongside this guide, see our free life cycle worksheets for all four organisms.

Life cycles for kids: a simple definition

A life cycle is the series of changes a living thing goes through from the start of its life until it can produce young of its own. Because those young then go through the same changes, the stages loop round in a circle, which is why we call it a cycle.

When you teach life cycles, four ideas matter more than any single fact:

• Start: animal life cycles begin with an egg; flowering plants begin with a seed.
• Growth: the young living thing feeds and gets bigger.
• Change: some living things change shape completely; others just grow.
• Reproduction: the adult makes eggs or seeds, and the cycle starts again.

Four life cycles compared: the stage-by-stage table

This table is the heart of our guide to life cycles for kids. We use one well-studied example for each group: the monarch butterfly, the common frog of the UK and Europe, a garden (French or bush) bean, and the domestic chicken.

Animal life cycles and plant life cycles share these four life cycle stages, but the timings differ. Sources are listed at the end. Notice the huge spread: a summer monarch can go from egg to adult in about a month, while a common frog needs two or three years before it can breed.

The butterfly life cycle: four stages and complete metamorphosis

Most lessons on life cycles for kids start with the butterfly, because the changes are so dramatic. Butterflies go through complete metamorphosis, which means four stages that look nothing alike: egg, larva (caterpillar), pupa (chrysalis) and adult. According to the Monarch Joint Venture, a monarch egg hatches in 3 to 5 days, the caterpillar stage lasts about 9 to 14 days in summer, and the chrysalis stage lasts 8 to 15 days.

What happens inside each stage

• Egg: the female lays single eggs on milkweed, the only plant monarch caterpillars eat.
• Caterpillar: it eats almost constantly and sheds its skin five times as it grows.
• Chrysalis: the caterpillar hangs in a J shape, sheds its skin one last time and the chrysalis forms. Inside, its body is rebuilt into a butterfly.
• Adult: the butterfly pumps fluid into its wings, dries off and flies away.

Summer adults live about two to five weeks. The late-summer generation that migrates can live up to nine months. Other species have different timings. Our butterfly life cycle printables let children cut, order and label the four stages.

The frog life cycle: from water to land

The frog is the amphibian in most life cycle units. Frogs are amphibians, so their life begins in water and ends partly on land. The Natural History Museum says common frog spawn takes around three weeks to hatch, and Froglife gives two to four weeks, depending on the weather.

Spawn, tadpole, froglet, frog

• Frogspawn: clumps of black eggs inside clear jelly, usually laid at the edges of ponds in late winter or early spring.
• Tadpole: fully aquatic, with gills for breathing underwater. It grows back legs, then front legs, while its tail is slowly absorbed.
• Froglet: lungs develop, so the young frog can breathe air and leave the pond. Suffolk Wildlife Trust puts the change from tadpole to froglet at about 14 weeks.
• Adult frog: common frogs are ready to breed at around two to three years old and live for about five to ten years.

The museum notes that cold water or plenty of food can delay metamorphosis by several months. Use our frog life cycle worksheets to practice the four stages and their vocabulary.

The plant life cycle: seed to seed

Plants are the odd one out: a flowering plant has no eggs or tadpoles, but it still follows a cycle: seed, germination, seedling, adult plant, flower, pollination, fruit with seeds, and seed dispersal. Beans are the classroom favorite because the seeds are big and they grow fast.

The University of Saskatchewan gardening guide says beans germinate in about 8 to 12 days when the soil is 15 °C or warmer, take two weeks or more in colder soil, and usually go from seed to harvest in 55 to 80 days, depending on the variety. Pods are ready about three weeks after flowering.

Why flowers matter in the plant life cycle

Children often think the flower is just decoration. In fact, the flower is where pollination happens, and pollination leads to seeds. Each bean pod is a fruit full of new seeds, so the cycle closes when a seed is planted again. The plant life cycle worksheets include a seed-to-seed diagram to label.

The chicken life cycle: growth without metamorphosis

The chicken is the bird example, and birds do not go through metamorphosis. A chick hatches looking like a small, fluffy version of its parents, then grows real feathers and gets bigger.

The University of Illinois Extension says fertile chicken eggs hatch about 21 days after they go into an incubator, which runs at about 100.5 °F (38 °C) in a still-air model. It gives about 17 to 18 weeks as the age when hens start laying. Breed, food and day length all affect this, so backyard hens can start later.

Egg, embryo, chick, adult

Inside the egg, the embryo uses the yolk as food until it hatches. Our chicken life cycle sheets cover egg, embryo, chick and adult hen.

Comparing life cycles: what is the same and what is different

Comparing life cycles is where real understanding shows, because children must explain why things differ.

Discussion question: which is most like a human life cycle? The chicken, because the young simply grow bigger without changing shape.

Life cycle stages in numbers: how long is each stage?

Pictures of life cycle stages hide how unequal the stages are. We added up the sourced ranges from the table above to see how the time is shared between stages. The monarch totals 20 to 34 days from egg to adult, the frog 112 to 126 days from spawn to froglet, the chicken 140 to 147 days from egg to laying hen, and the bean 55 to 80 days from seed to ripe pods. The shares use the midpoint of each range:

A monarch spends about 43% of its time as a caterpillar and another 43% as a chrysalis, but only 15% as an egg. A frog spends 82% of the time to froglet as a tadpole, and a chicken spends about 85% of the time growing from chick to laying hen.

These numbers answer a question children often ask about animal life cycles: why does the young stage look so long? In most cycles the young stage is where nearly all of the growing happens, while the egg or seed stage is short. For comparing life cycles, ask children to draw each stage as a slice of a circle, with the size of the slice matching its share. The butterfly circle will be split into thirds, and the frog and chicken circles will be mostly one large slice.

Teaching life cycles for kids by age and grade

The same four examples work from preschool to upper primary. What changes is how much detail you expect. In England, the national curriculum for science asks Year 2 students to notice that animals have offspring which grow into adults, Year 3 students to explore the part flowers play in the plant life cycle, and Year 5 students to describe the differences between the life cycles of a mammal, an amphibian, an insect and a bird.

• Ages 3 to 5 (preschool, Reception): order three or four big picture cards and say “first, next, last”.
• Ages 5 to 7 (Kindergarten to Grade 1, Years 1 to 2): label the four stages of each life cycle, and match babies to adults (tadpole to frog, chick to hen).
• Ages 7 to 8 (Grade 2, Year 3): grow beans and draw the plant life cycle with flower, pollination and seed dispersal.
• Ages 9 to 11 (Grades 4 to 5, Years 5 to 6): compare life cycles with a table like the ones above, use the terms metamorphosis, larva, pupa and embryo, and explain why timings vary.

Hands-on life cycle activities

1. The bean-in-a-jar diary (ages 5 to 10)

This is the most reliable experiment for life cycles for kids, because beans sprout within about two weeks indoors.

1. Line a clear jar with damp paper towel and slide two bean seeds between the paper and the glass.
2. Keep the paper damp and the jar somewhere warm, but out of strong sun.
3. Every two days, draw what you see and measure the root and shoot.
4. Plot the shoot height on printable graph paper to make a simple growth chart.
5. Once leaves open, plant the seedlings in compost so they can grow on to flower.

2. Life cycle wheel (ages 5 to 8)

A wheel shows that life cycles really are circles. Cut two paper circles. Divide the bottom one into four parts and draw a stage in each. Cut a window in the top circle and join them with a brass fastener, so turning the wheel shows one stage at a time. The cut-and-paste practice on our cut and paste worksheets builds the scissor skills this needs.

3. Write a life cycle story (ages 7 to 11)

Children write “A week in the life of a tadpole” or “My 21 days inside an egg” on story paper with a picture box. Ask them to include at least three correct facts from the comparison table.

4. Pond watch (all ages)

In spring, visit a pond with frogspawn and photograph the same spot every week instead of taking spawn home. Children see that real life cycles for kids rarely match the book exactly, because weather changes the timing.

Common mistakes when teaching life cycles

• Calling a chrysalis a cocoon. Many moth caterpillars spin a silk cocoon; butterflies form a chrysalis without silk covering it.
• Saying a chick goes through metamorphosis. It does not. It hatches with the same body plan as the adult.
• Giving one exact number. “Frogspawn hatches in 3 weeks” is a typical figure, not a fixed rule. Teach ranges.
• Stopping the plant cycle at the flower. The cycle only closes when new seeds form and are spread.
• Drawing a line instead of a circle. If the adult does not point back to the egg or seed, it is a timeline, not a cycle.
• Thinking tadpoles have lungs from the start. They breathe with gills, and lungs develop as they change into froglets.

A quick life cycles quiz for kids (with answers)

1. What is a butterfly called during its second stage? Answer: a caterpillar (larva).
2. What do tadpoles use to breathe underwater? Answer: gills.
3. About how many days does a chicken egg take to hatch in an incubator? Answer: about 21 days.
4. What part of a plant turns into a fruit full of seeds after pollination? Answer: the flower.
5. Which of the four does not go through metamorphosis: butterfly, frog or chicken? Answer: the chicken.
6. What is the only plant monarch caterpillars eat? Answer: milkweed.

For more questions like these, try our science trivia for kids or the online animal quiz.

Related guides and printables

• Printable life cycles for kids: butterfly, frog, plant and chicken worksheet sets
• Science worksheets for every grade
• Sequencing and graphic organizers for writing up a life cycle
• How to improve concentration in kids during longer science projects
• Graph paper sizes guide for plant growth charts

Sources

The timings in this guide to life cycles for kids come from these sources. Monarch: Monarch Joint Venture, Life Cycle. Common frog: Natural History Museum, Froglife and Suffolk Wildlife Trust. Beans: University of Saskatchewan. Chickens: University of Illinois Extension. Curriculum: Department for Education, science programmes of study.

Frequently asked questions

7 quick answers

What are the 4 stages in life cycles for kids?

For most animals, children learn four stages: egg, young, a changing or growing stage, and adult. For a butterfly that is egg, caterpillar, chrysalis and butterfly; for a frog it is frogspawn, tadpole, froglet and frog.

What is the difference between complete and incomplete metamorphosis?

Complete metamorphosis has four stages (egg, larva, pupa, adult), as in butterflies and beetles. Incomplete metamorphosis has three (egg, nymph, adult), and the nymph looks like a small adult, as in grasshoppers.

Which of these life cycles is the shortest?

The butterfly. A summer monarch can go from egg to adult in about a month, while a chicken takes months and a common frog two to three years to start breeding.

Does a chicken go through metamorphosis?

No. A chick hatches with the same body plan as an adult chicken. It grows feathers and gets bigger, but it does not change shape the way a tadpole or caterpillar does.

How do you explain life cycles for kids in preschool?

Use three or four large pictures and the words first, next and last. Start with the butterfly, as the changes are easy to see, then let children put the pictures in a circle.

Why do timings in life cycles vary so much?

Temperature, food and species all matter. Warm weather usually speeds development up, cold slows it down, and different species of butterfly, frog or bean have their own typical timings.

Which stage of the life cycle is the longest?

In the examples here it is the young stage: about 82% of the time from frogspawn to froglet is spent as a tadpole, about 85% of a chicken’s time to laying is chick growth, and a monarch spends about 43% of its time as a caterpillar.