Lesson #3: Leaves
This week’s lesson will focus on leaves, the plant part that harvests light for photosynthesis. Students will begin this lesson by reviewing the various plant parts- fruits, seeds, stems, roots, leaves, and flowers. They’ll then brainstorm together to develop a list of the leaves humans eat and learn why they’re are an important part of a healthy diet. Students will then have the opportunity to prepare their own personal salads using a variety of leafy green vegetables paired with healthy toppings and dressings.
Main Idea:
Leaves can have a variety of tastes and textures.
Objectives:
SWBAT Identify the parts of a plant and their functions.
SWBAT rip leaves for salads.
TEKS:
10 (A) explore how structures and functions of plants and animals allow them to survive in a particular environment.
Materials:
- Plant parts sort cards
- A variety of edible leaves
- Taking a Look at a Leaf, 1 per student
- Small Bowls or plates
- Forks
- Large mixing bowls (1/group)
- Salad dressing
Prep:
Print plant sort pictures. Cut out individual pictures to create sets for each group in the class. Store with paperclips or in plastic baggies.
Print “Taking a Look at a Leaf”, 1 per student
Timeline (1 hour total):
5 min Introduction
10 min Plant Parts Sort
10 min Edible Leaf Investigation
10 min Make It – Ripping lettuce
5 min Salad dressing demo OR just toss lettuce in dressing
10 min Taste It – Salads
10 min Clean-up
Procedure:
- Review the parts of a plant and the associated functions from the previous week.
- Plant Parts Sort. Break up students into pairs. Give each pair the cut up plant pictures. Each of these plants has a part that people eat. Have the students sort the plants by part of the plant that we eat. Try to give them as little guidance as possible, encouraging them to discuss with their partner how to categorize the plants. When students have finished the sort, go over the plants as a class and discuss how they categorized each food.
- Fruits – squash, blueberry, raspberry, strawberry, pineapple
- Seeds – wheat, corn, green beans, pecan
- Stem – celery, onion (actually a modified stem, not a root), asparagus
- Leaves – spinach, lettuce, cabbage
- Roots – potatoes, carrots, beets
- Flower buds – cauliflower, broccoli
- Edible leaf investigation. Review the functions of plant leaves with your class. Ask your students if they can think of any edible leaves that people like to eat. Make a list on the board. Explain that leafy greens are part of a healthy diet:
- A diet high in leafy greens helps to reduce the risk of cancer and heart disease due to their high content of antioxidants
- Leafy greens are high in Vitamin A, C, E, and K and many of the B vitamins
- They are low calorie and low on the glycemic index
Tell students that today they are going to investigate five different types of edible leaves, by tasting, smelling, measuring, and observing. Organize students into groups of three or four and have them wash their hands before sitting in their seats. Distribute worksheets to each student and tell them that they will be using the “Taking a Look at a Leaf” worksheet for the next part of the lesson. Show your class one edible leaf. Demonstrate how you would like each group to observe the color, texture, smell, taste, and length of each leaf in the chart. Examples of texture could include smooth, fuzzy, bumpy, sandpapery, slippery, etc.
Be sure to discuss possible vocabulary with your students before they begin describing leaf texture, smell, and taste. Distribute a washed sample of a different leaf to each group and guide them through the data collection. When students have recorded data in their charts, instruct them to tear off a small piece of the leaf to taste. As a class, review the various results for each leaf type.
- Tearing lettuce leaves for salad. To make a salad, you don’t even need a knife! Demonstrate how to rip salad leaves to students before giving them a new set of salad leaves. Students will each tear up their own piece of leaf for the salad.
- Taste it – Salads. Have students put their own leaves on their plates to make their own salads. Offer additional pre-cut vegetables, such as carrots or tomatoes, to add to their leaves. Top with dressing.
- Clean-Up – Students will return the classroom to its previous state, including washing cutting boards and knives, and wiping down tables and floors as necessary.
Supplementary Materials: