FOCUS: Dandelion flowers serve the same function as all other flowers: to produce seeds for the next generation. Whether you consider them wildflowers or weeds, these hardy plants are here to stay, and they provide an important food source for birds, bees, and other animals. We’ll dissect simple flowers to see how seeds develop and compare these to the complex structure of dandelions. Outside, it’s easy to find examples of dandelions in all stages of development and get a first-hand view of the progression from flower bud to fluffy white seed head. You and the wind can help spread their parachute seeds far and wide.
Objective: To begin to explore and ask questions about dandelions.
Give each small group of children a variety of flowers, including a dandelion, and ask children to talk about what they notice about the different flowers.
Materials: an assortment of flowers, including dandelions; magnifying lenses.
Objective: To investigate a flower’s structure, sorting the parts and looking for patterns of similarities and differences.
Give each pair of children a simple flower, such as a Peruvian lily (Alstroemeria), daffodil, or tulip, and a magnifying lens. It is helpful if everyone has the same kind of flower. First, ask the children to observe their flowers and share things they notice and wonder about, making note of their questions. Have the children turn the flower upside down. Starting with the outermost layer, have them remove the parts in each concentric ring, putting similar parts together. (To see which is the outermost ring, look at a bud, or gently gather the petals of an open flower together as they would have been in bud, to see which are on the outside.) As they dissect their flowers, name and describe each flower part and its function. Provide older children with four index cards – labeled Sepals, Petals, Stamens, Pistil(s) – on which to place flower parts as they remove them.
Stem – holds up the flower
Sepals (outermost ring of flower parts) – protect the bud; usually green but can be the same color as petals
Petals (next ring of flower parts) – attract pollinators, often giving them a landing place; often colorful, may also make scent and/or nectar
Stamens (next ring of flower parts) – produce and hold the pollen, made up of a filament (the stem), anther (the canoe-shaped structure at the tip that holds the pollen), and pollen (the tiny grains on the anthers)
Pistil(s) (at center, may be one or more) – act as catcher for pollen, container for the ovule(s). Pistil is made up of the vase-like ovary, the stem-like style, and the sticky stigma at the top of the style
Ovules (found inside the ovary, often look like tiny white beads) – become the seeds when fertilized by pollen that has landed on the stigma
- Count the number of parts. How many are there of each part? Do they notice a pattern? (Lily Family flowers have three sepals and three petals, six stamens, a three-lobed stigma and three-sectioned ovary – all parts in threes or multiples of three.)
- Look for color patterns such as lines, spots, or stripes on petals; find pollen grains and observe their color.
- Tear or cut open the base of the pistil to find the ovules (use fingernails, or an adult may do this with a small knife). It is helpful to open some lengthwise and some crosswise. What will each ovule eventually become? (A seed.)
Materials: for each child or pair of children: magnifying lens; a Peruvian lily (Alstroemeria), daffodil, or tulip; for older children, four large index cards labeled Sepals, Petals, Stamens, and Pistil(s); small knives for leaders, Flower Parts diagram.
BUILD A FLOWER
Objective: To use a model to review the parts of a flower and their arrangement.
Have the children work in small groups, and give each team a felt board and felt flower parts. Review each of the parts learned in the previous activity while dissecting real flowers. Have the children use their flower parts to create a felt model of a flower. Hold up their felt boards for all to see. Did all groups construct their models in the same way? Did some put petals and sepals below the ovary and others put them above? Compare to a Flower Parts diagram and point out that ovaries can be above or below the sepals and petals in different kinds of flowers.
Now the leader, or a child from each team, gets a bee puppet, which collects pollen from one felt flower and buzzes over to another flower, dropping it off on the pistil and picking up some of that flower’s pollen to take on to the next flower she visits. Make sure that every felt board flower gets pollinated. As each flower receives pollen, have a pollen grain travel down the style and meet the ovules; then the children change the ovules into brown or black seeds. Once the seeds are developing, does the flower need pollinators anymore? Now that their job is done, what happens to sepals, petals, and stamens? (They usually fall off, so children can remove them from their model.) What happens to the pistil as the seeds grow? (Gets bigger.)
Materials: for each group: felt board, felt flower parts, honeybee puppet, Flower Parts diagram.
UPPER GRADES CHALLENGE: Dandelion Countdown (Grades 4-6)
Objective: To investigate the number of florets in a dandelion flower head.
Ask students how we could determine the number of florets in a typical dandelion flower head. Have students examine a few dandelion flower heads in full bloom and make some guesses about the number of florets in each. Write these on the board for all to see. Then, give each student a half-sheet of black paper. Divide a dandelion flower head into small sections and give one section to each student. (A single flower head can be divided among several students as it may have from 175-300 florets.) Have each student gently separate the florets and count them. It is helpful to cluster them in groups of ten to make counting easier. Afterwards, add up the students’ totals for each flower head. Compare the total to the student’s estimates.
How many seeds will a dandelion flower head produce? (The same number as its florets.) How many seeds could a dandelion plant produce in a season? What are some reasons why this might be advantageous to a plant?
Materials: a few large dandelion flower heads in full bloom; half-sheets of black paper, one per student; white board and marker; optional: calculator.
DISSECT A DANDELION
Objective: To investigate a dandelion flower, looking for similarities and differences compared to simple flowers.
Have children work in pairs or small groups. Give each team a small piece of black paper and a dandelion flower to study. Explain that what we think of as a dandelion flower is not one flower but many small flowers called “florets” grouped together. Have them look at the intact flower head first before taking it apart, noticing the green bracts at the base (these are not sepals but modified leaves), the yellow petals, and the curlicue stigmas sticking up above the yellow petals. Now show them how to carefully pull apart the flower head to separate out a single floret. Be sure each child has a magnifying lens to examine the florets. Provide copies of the Dandelion Floret diagram and have them try to find all the parts:
- Petal – called a strap; it has a jagged edge at the top with five tiny teeth
- Ovary – the small, white, seed-shaped base of the floret which will become the seed
- Pappus – the fuzzy white hairs above the ovary, which are modified sepals and will become the parachute of the seed
- Style – the thin stalk that lies inside the petal
- Stigma – the curlicue top of the style
- Anther tube – the darker yellow, slightly thickened area on the style. This holds the dandelion’s pollen
- Pollen – the yellow grains that drop onto the black paper
Can they find all these parts? Take guesses about how many florets there might be in a dandelion flower.
Materials: dandelion flower heads, black paper, magnifying lenses, Dandelion Florets Up Close diagram.
GOING TO SEED (Grades K-2)
Objective: To look outside for evidence of the various stages from bud to seed in a dandelion plant.
Bring the children outside to a place where there are dandelions growing. Beforehand, punch four to five holes in a circle around the center disk of small paper plates, one per child. Pass out the plates and tell the children to look for four to five different flower stages. Have them place their flower stage samples into the holes in their plate in order of age to illustrate the life cycle of a dandelion flower from bud to seed head. Have them use the Beauty Before Age cards as a reference to confirm the order of their stages, then use tape to secure them firmly in place. (Note: in early May it may be difficult to find mature seed heads.)
Materials: Beauty Before Age cards, paper plates, tape.
Objective: To investigate variation in leaf design in a population of dandelions.
Bring the children outside to a place where there are dandelions growing. Have everyone pick two leaves, trying to collect these from as many different plants as possible. Send groups to different areas of the school grounds, such as shaded or sunny, mowed or unmowed, etc. Lay the leaves out on a white sheet to see any variation in size, shape, and toothed edges. What patterns do the children notice when comparing leaves from different locations? What could cause the difference? If time permits, have children collect another set of leaves to test a theory they suggest.
Materials: white sheet; optional: rulers.
Comparing Stem Heights of Buds, Flowers, Seed Heads
Objective: To investigate and compare the heights of dandelion buds, flowers, and seed heads.
Ask the children whether there might be a difference in the heights of flower stems with buds, flowers, or seed heads. How could we find out? Have every child pick two dandelion buds, two flowers, and two seed heads, making sure they pick each sample from its very base and collect the whole stem. Have the children lay out their collections on a white sheet in three groups: buds, flowers, and seed heads. Line up each group of flower parts from shortest to tallest to measure them. Do they notice a pattern in the height of buds versus flowers versus seed heads? Have the older children measure ten samples from each group and calculate an average height for each. Which has the tallest specimens – buds? flowers? or seed heads? Why might seed heads be taller (on average) than buds and flowers? (To expose seeds to the wind.)
Materials: a white sheet or shower curtain, rulers; optional for older children: calculators
BEAUTY BEFORE AGE
Objective: To model the cycle of development from bud to seed in a dandelion.
Beforehand, make two sets of the Beauty Before Age cards. Divide the children into two groups and explain that you will be giving everyone a dandelion photo card that depicts a stage in a dandelion’s life cycle. Each group must line up in order, from the earliest stage to the latest. For the older students, challenge them to do this without talking. When all groups are lined up, ask the first child from each group to reveal and compare their cards. Continue down the lines, discussing the stages of the dandelion’s life cycle. Close the activity by having each line form a circle, to model the cyclic pattern of a dandelion’s life.
Materials: Beauty Before Age cards, two sets.
Objective: To draw a dandelion using the plant pigments as the art medium.
Have the children draw a dandelion in their journal, complete with flower head, stem, and basal rosette of leaves. Have them color in their flower head by twisting an actual dandelion flower head back and forth in a circle on their drawing. Rub dandelion leaves over the drawing to color the leaves green. Share their pictures with others in small groups.
Materials: journals or paper and clipboards, pencils, dandelion flowers and leaves.
PUPPET SHOW “Dandelion Defenders”
Objective: To learn why dandelions are so successful and how they are important to some animals.
Perform the puppet show, or have a group of children perform it for the class. Afterward, ask questions to review key details and vocabulary in the story. What are dandelions and other flowers for? (Making seeds for the plant.) What makes it hard to pull up dandelions? (Long taproot, root hairs that hold the soil.) Why are they hard to mow? (Stems lie down, flowers grow on shorter stems.) How are dandelions important to animals? (Provide food in early spring for deer, rabbits, woodchucks; provide honeybees with nectar and pollen.)
Materials: puppets, script, props, optional: real dandelion seed head.
Objective: To review and share some thoughts about dandelions.
Have each child pick a dandelion flower. Gather the children into a circle, sitting on the grass. Show them how to make a dandelion chain, using the Dandelion Chain Instructions provided. Have every child share one thing they learned about dandelions and then add their dandelion to a group dandelion chain. Ask for suggestions of where to place the chain when you’re done.
Materials: Dandelion Chain Instructions; dandelion flowers, one per child.
A STEP BEYOND
Visitors to a Dandelion Have children spend time quietly observing dandelions when they are in bloom to see what insect pollinators visit them. Keep a photo record of the insects they see each day. How many different insects did they see in a week?
Potting Dandelions Plant dandelion seeds in pots and keep them watered. Cut one-inch pieces of a dandelion root and plant these in other pots. Keep records of sprouting time and watch the plants develop. Which were more successful at sprouting? Which grew faster?
Daily Dandelion Observations Have children select dandelion plants outside to study. Visit them daily and record changes as they occur with drawings or photos. What are some of the changes they notice over a week or two of observations?
Dandelion Marmalade Find a recipe and make dandelion marmalade.