For today's lesson, we are going to backtrack a bit to define and investigate the functions of various plant parts. Let's learn more about roots, stems, leaves, flowers, and fruit.
In the book Seed to Seed: The Secret Life of Plants Nicholas Harberd talks about some of the early childhood experiences he had that influenced him to become a plant geneticist. For example, he remembered the teacher "forcing" horse chestnut tree branches in the classroom, causing the leaf buds to swell and unfurl into leaves. He also vividly recalled his father digging parsnips and his own realizations about plants having roots underground. Simple activities with plants like these can have lasting impacts.
Activity: Edible Plant Parts.
Discover what are the parts of a plant and how they relate to vegetables we eat. This can be done informally at home during the preparation of a salad, or more formally in a classroom.
• Potted mint plant or other conveniently-sized herb or vegetable, with flowers if possible (optional)
• Plastic bin or tray to catch soil from potted plant (optional)
• Spinach and/or lettuce leaves
• Broccoli and/or cauliflower
• Radish and/or carrot (preferably with tops intact) - Avoid baby carrots
• Green beans and/or peas
Have enough pieces so children may explore the vegetables and have enough left over to make a salad.
1. Explain plants have different parts/structures that do different jobs for the plant.
2. Ask the children to identify the parts of the potted plant. Place the plant in the bin or tray and gently remove the pot to expose the roots.
3. Brainstorm about about what the function of each part might be.
a. roots- take up water and nutrients, anchor the plant so it can stay upright
b. stem- move water and nutrients from roots to leaves and flowers, support leaves so they are exposed to sunlight (What would happen if all the leaves were laying on the ground?)
c. leaves - use the energy from sunlight to make food for the plant
d. flowers- attract pollinators, make pollen, develop into fruit
e. fruit - ripened part of flower (ovary) that holds the developing seeds
f. seeds - contain the stored food and embryo that, given the proper conditions, could become a new plant.
4. Return the potted plant to its pot or plant it in a garden when the lesson is finished. Have the children was their hands.
5. Distribute the vegetables and have the children identify the parts of the plants that are represented.
• Spinach and/or lettuce - leaves
• Broccoli and/or cauliflower -stem and flower bud
• Celery - the base is the stem, the stalk is a petiole, leaves
• Radish and/or carrot (preferably with tops intact) - roots, those with tops will have stems and leaves as well
• Green beans, peppers, and/or peas - technically fruit with seeds inside. Open the pods to see the seeds inside.
6. If appropriate, wash the vegetables and make a salad for everyone to share.
Extension: Challenge older students with some vegetables that are more difficult to classify.
• Onion (bulb )- each layer of in an onion bulb is a fleshy leaf base, attached to a short stem. Often the roots are visible on the bottom, too.
• Potato - because it grows underground, children may guess a potato is a root, but botanically it is a modified stem.
• Sweet potato - on the other hand, the sweet potato is a tuberous root.
To help explain the difference between the sweet potato and regular potato, ask the children to think about where a new plant would sprout. The sweet potato will only sprout from the top, where the stem was attached. The potato will develop sprouts wherever there are “eyes.” The eyes are buds on a stem.
To see our complete plant science lessons, either visit the plant science category (newest posts to oldest posts) or the plant science section of our experiment archive page (links to posts in order).
For more activities, try our Gardening/Plant Science for Kids Pinterest board.