FOCUS: By summer’s end, nearly every leaf bears some signs of feeding by plant-eaters small or large. Some make holes, some scallop the edges, some roll the leaves into tubes. Plants capture energy from the sun and, in turn, produce food for a variety of leaf-eaters. When we watch a leaf-eater feeding on a leaf – or being eaten by a predator – we are seeing the flow of energy from sun to plant to herbivore to carnivore. These interactions are evidence of food chains and webs, important components of every ecosystem.
Objective: To begin to explore and ask questions about leaf-eaters.
Bring in or have children gather a variety of leaves that have bite marks, spots, or irregularities on them. In small groups, ask children to sort their leaves according to their observations.
Materials: a variety of leaves with bite marks, spots, or irregularities.
SORTING LEAF-EATER PATTERNS
Objective: To view examples of leaf-feeding, noticing patterns and grouping by shared characteristics.
Begin by giving each small group of children a set of photos of leaves showing damage by leaf-eaters (Leaf Photo Set). Ask them to look for patterns of similarities and differences and sort the leaves into several groups by the kind of damage they notice. Next, introduce the Leaf-Eater Patterns cards with drawings that illustrate damage from a leaf-miner, hole-maker, edge-feeder, leaf-roller, skeletonizer, and leaf-wrinkler. Discuss differences in the leaf damage and how it comes about. Now have them re-sort their cards using the six categories in the drawings.
Materials: Leaf-Eater Patterns cards; Leaf Photo Set: 24 photos of leaves with leaf-eater damage; optional: photos of leaf-eating insects.
LOOK AND LISTEN
Objective: To sit quietly, observing signs of leaf-eaters and other animals on the school grounds.
Take children outside and find a spot for each child to sit where he or she cannot touch another child, preferably where there is some vegetation like grasses, bushes, or trees. Ask them to sit very quietly noticing any nibbled leaves or live animals, like birds overhead, insects on leaves or flowers, spiders in webs or on leaves, ants or beetles on the ground. Older students may want to record their observations in their science journals. After a few minutes, call them back to a circle to share observations. What evidence of leaf-eaters or other animals did they notice? Why might these animals be on or near the plants? (To feed on them, look for prey, lay eggs, etc.)
Materials: optional: plastic bags to sit on if ground is wet; for older students: science journals or clipboards and paper, pencils.
Objective: To look for and collect leaves with evidence of various leaf-eating or shelter-building insects or spiders.
Have young children work in small groups with a leader and older children in pairs, to look for any signs of leaf-eaters on or near the school grounds. Look in different areas such as tall weeds, trees on or along the edges of the playground, shrubs, and school gardens. Look for examples of each pattern of leaf-eating shown on their Leaf-Eater Search card. Each group may collect one of each type of leaf pattern, as long as there are no animals on or hiding in the leaf. Have them draw or make a note of any living creatures they find on or inside leaves to share with the group.
What sign of a carnivore (spider on web, ant carrying prey, other) did you see?
Have children hold up their examples of each leaf-eating pattern as an adult calls them out. You may want to save these leaves in the pages of a notebook for a later journal activity. Which patterns were the most common? Were any patterns hard to find? What interesting leaf inhabitants did they find? Could any of these be animals that feed on the leaf-eaters? Why do they think so? How could we find out?
Materials: Leaf-Eater Search card, one for each group; science journals or clipboards and paper, pencils.
PUPPET SHOW “Leaf-eaters and Their Foes”
Objective: To meet some leaf-eaters and learn about the flow of energy through food chains in an ecosystem.
Perform the puppet show, or have a group of children perform it for the class. Afterward, ask questions to review the key details and vocabulary in the story. What do we mean by ecosystem? (All the living and nonliving things in a place and all the ways they are connected.) What is a habitat? (The place where an organism lives and where it gets its food, water, shelter, and space to rear its young.) What’s an example of a habitat from the puppet show? (Grasses live in fields.) Why are plants called producers and animals called consumers? (Because plants can make food and animals have to eat food.) What kind of leaf-eater was the caterpillar? (Hole-feeder.) What kind of leaf-feeder was the grasshopper? (Edge-feeder.) What role do leaf-eaters play in an ecosystem? (They eat plants and are food for birds and other animals.) What are the parts of a food chain? (Plants, plant-eaters, meat-eaters.) What is an example of a food chain found in the puppet show? (Leaf-caterpillar-bird, grass-grasshopper-fox.) Hold up the puppets to show each food chain. Where does the energy come from for plants to make food? (The sun.)
Materials: puppets, script, stage.
FOOD CHAINS AND WEBS
Objective: To model how plants and animals in an ecosystem are connected in a complex food web.
Make up a set of Food Web cards on colored cardstock with the following plants and animals on them. Food preferences are listed on each animal card.
Food Web Cards:
Color 1: Wild Strawberry – Mouse – Snake
Color 2: Milkweed – Butterfly – Spider
Color 3: Grass – Deer – Coyote
Color 4: Clover – Woodchuck – Fox
Color 5: Goldenrod – Bumblebee – Skunk – Great-horned Owl
Color 6: Dandelion – Rabbit – Red-tailed Hawk
Color 7: Maple leaf – Caterpillar – Chickadee
Hand out a Food Web card to each child. Ask the children which of them are producers (plants), which are herbivores (plant-eaters), and which are carnivores (meat-eaters). Now ask children to form themselves into food chains, by finding others with the same color cards and arranging themselves in order (producer, herbivore, carnivore). Ask the children where the energy comes from for plants to produce food? (The sun.)
Optional: Have children sit down, staying in their food chains. An adult acting as the sun (wearing a badge or costume) passes out a bag of healthy snacks to each producer; producer takes a snack and passes the bag on to the herbivore and then the carnivore in each line, to represent how matter flows through a food chain, giving every organism the energy it needs to live and grow.
For grades 3-6: Point out that in an ecosystem, most living things are part of many different food chains. Have the children sit in a circle holding their food web cards in front of them. Ask children to look around the circle and think of ways they might be connected to other animals and plants. Use yarn to make the connections, as children suggest them, continuing until the yarn begins to form a tangled web. Point out that the animals and plants in an ecosystem are interconnected in many ways, forming a complex food web. Tug on or lift a strand to show how a change in one part of an ecosystem can have an effect on other parts.
Materials: Food Web cards of plants and animals as listed above, one for each child; ball of yarn or ten eight-foot pieces of yarn rolled up; optional: tape or string for cards, bags containing healthy snacks, sun costume.
Objective: To notice and record patterns of leaf-feeding in a leaf collected on the school grounds.
Have each child select one leaf showing evidence of a leaf-eater, or use leaves saved from the Leaf-eater Search, and make a drawing of it in their journals. Afterward, in small groups, have children show their drawings and share their ideas about how this pattern could have come about. Or have them switch drawings with another child and try to find the matching leaf.
Materials: science journals or clipboards and paper, pencils; optional: colored pencils.
UPPER GRADES CHALLENGE: Schoolyard Haiku (Grades 5-6)
Objective: To use poetry to record thoughts and observations of the ecosystem on the school grounds.
Explain to the students that a haiku is a traditional Japanese form for a poem that was intended to improve awareness of nature. It has some simple rules:
- A haiku has three lines.
- The first line has five syllables, the second has seven, and the third has five.
- It should stay in the present tense, talking about what’s happening right now.
- It should not rhyme.
- It should not contain metaphors (the moon is a pizza pie) or similes (dewdrops are like pearls).
- It should contain a clue to the season. (Words like “forest” or “moon” refer to nature, but they don’t indicate season. Words like “firefly” or “daylily” tell you it is summer.)
- It should use specific images, like “yellow lily,” instead of general ones like “flower.”
- It should show what you notice with an image rather than explaining in detail. For example, instead of saying “I saw a bird,” try “Bluebird on a post.”
- It can express any emotion, be humorous, sad, cheerful, or just quietly observe something about nature.
Here are a few examples by Japanese haiku masters. Because they are translations, they vary from the exact syllable counts:
A giant firefly
That way, this way, that way, this
And it passes by
— Basho, 1644-1694
That autumn has come
I was convinced:
— Buson, 1716-1783
Have children find places to sit quietly by themselves and compose their own haiku. Ask them to think about and notice what’s happening around them in the natural world and any ecosystem interactions they observe. Afterward, give everyone a chance to read their haiku out loud. Shy writers may pass or ask someone else to read their poems. Leaders can set a good example by reading their own poems.
Materials: journals or clipboards and paper, pencils.
Objective: To reflect on the discoveries made while investigating leaves and leaf-eaters.
Have each child complete this sentence: My favorite find today was ______because______.