Lesson 4: Plant Classification

• Students will understand how plants are classified.

All plants are made up of similar parts, but they often look different. Like animals, those that look more like each other than any other plant belong to the same species. Plants can be classified as grasses, herbaceous plants, woody shrubs, and trees.

• Grasses have slender leaves and reproduce by sending out underground rhizomes.
• Herbaceous plants have leaves and stems that die at the end of the growing season.
• Woody shrubs have stems that are covered by a layer of bark.
• Trees are woody shrubs that have a main trunk and many branches.

• Plant cards drawn by students in Unit 1, Lesson 2.
• Notebooks and pencils

• Classification: the arranging of groups of organisms into categories based on certain characteristics

1. Using the plant cards that the students have drawn, have students group them by similarity based on different characteristics. For example, make a group of plants that have flowers and one of plants that puts out runners or tillers. This will illustrate the notion of “classification.”
2. If possible, invite an elder from the community to this class. Have the children explain how they grouped the plants. Ask the elder to explain to the students how he/she would group them and compare the two systems of classification to see if they are different and if so, how. Ask him/her to share any stories based on indigenous knowledge. If no elder is available, ask the students to discuss their classifications at home with their parents and grandparents to compare.

​Plant Biodiversity

Objectives

• Students will understand that their environment is full of many plant species.
• Students will be able to compare the biodiversity of plants in different areas and think about why differences in biodiversity exist.

Background

Different areas have different levels of plant biodiversity. Biodiversity refers to the amount of variation between different species. Here are some of the main reasons biodiversity is important:

• It is important to conserve the diversity of life to provide communities with useful products. Plants and animals could provide us with additional foods, medicines, and other products that will save lives and benefit our community.
• It is important to protect the diversity of life because biodiversity helps maintain important life and systems processes such as oxygen production, pollination, and flood control that, in turn, help support all life on Earth.
• Our lives would not be as rich if we lost species such as Grevy’s zebra, beetles, hawks, frogs, lizards, lions, and leopards, and the habitats where they live. The rich diversity of life also allows for important recreational activities such as walking safaris, game viewing/watching, game-bird shooting, camping, and bird-watching. (Many of these activities are part of ecotourism.)
• It is important to protect the diversity of life because no generation has the right to destroy the environment and resources on which future generations depend. It is our responsibility to take care of the diversity of life for future generations.
• It is important to protect the diversity of life as it provides inspiration and provokes curiosity and imagination. Art, music, and poetry are often inspired by Earth’s diversity. And many of our technological advances, such as flight, have been inspired by nature.
• It is important to protect the diversity of life because all species have a right to exist. Humans are not the supreme deity that should determine the fate of other inhabitants on our planet, but are just one member of the incredible assemblage of life on Earth.

Materials

• Plastic bags
• Water bottles
• Beads, pasta, beans, seeds
• Paper and pencils

Vocabulary

• Biodiversity

Procedure

1. Start by explaining that the environment is full of many plant species. These plants are used for many things including food, medicine, and shelter.
2. Ask students if they know the definition of the word “diversity” (“things that make people different”). Point out different levels of diversity in the classroom (girls and boys, skin color, types of clothing, etc.). Explain that biologists like to determine how diverse the environment is, and this is called biodiversity. Instead of counting the number of boys and girls, biologists count the number of species.
3. Take out water bottles that display different levels of biodiversity using seeds, beads, pasta, and beans. Each water bottle should have significantly different levels of biodiversity. Divide the students into groups and give each group a water bottle. Ask the students to empty the water bottle and create a histogram (one row for each “species”). Bring the class together and have the students compare their graphs. Ask them which graph has the highest level of biodiversity and which graph has the lowest. Talk about the benefits and drawbacks of different levels of biodiversity.
4. Divide the class into two groups. One group will observe the biodiversity outside of the schoolyard, and one group will observe the biodiversity within the schoolyard. Before class determine the two separate areas and decide how many steps the students should take between recordings. Have the students line up a few feet apart. Together, count out the number of predetermined steps and stop. Have the students look down and collect a sample of any plants they are touching. The teacher should then walk down the line with a plastic bag and the students can drop their samples in the bag. Repeat this for the rest of the area.
5. Return to the classroom and empty the contents of the two bags in separate areas of the room. Ask the students to group together the same species of plants. Record the types of species found and the number of each species. If possible, use field guides to identify the specific plants. Bring the class together and compare the two groups. There should be more biodiversity outside of the schoolyard. Ask the students to think about why biodiversity might vary.