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Japan's Secret Garden

Classroom Activity

To classify insects as helpful or harmful to society by collecting, analyzing, and interpreting information.

Materials for each team
  • copy of "Insects: Villains or Heroes?" student handout (HTML)
  • posterboard or art paper
  • reference books, magazines, and Internet access for research
  • art materials, such as markers or crayons, rulers, and scissors
  1. Discuss the characteristics of insects. (See Activity Answer for more information.)

  2. Give each student a copy of the "Insects: Villains or Heroes?" student handout.

  3. Ask the class to brainstorm a list of insects. List these on the chalkboard or on an overhead transparency for students to see. Add any to the list that students might not have considered. These can be found in print reference materials or on one of the suggested Web sites.

  4. Allow students to select one of the insects from the list to research but try to make sure that only one student is researching any one insect.

  5. Brainstorm with students the information they need to find out about their insect, such as common name; kingdom, phylum, class, and order; physical description; habitat; food source; carnivore or herbivore; special conditions needed for reproduction; and lifespan.

  6. Provide access to reference materials, including the Internet if possible, for students to find the necessary information about their insects.

  7. Have students determine the helpful and/or harmful aspects of their insect.

  8. Organize students into groups and have them report on the aspects of their insects. Once they have reported, have students determine which argument is most persuasive and why, and create a Wanted Poster or Certificate of Achievement based on their conclusions.

  9. Display all completed work, giving students an opportunity to justify their classifications of the insects they researched.

  10. Conduct a class discussion to measure agreement or dissatisfaction with the classifications.

Activity Answer

Insects are the largest class of the phylum Arthropoda. Their class within the phylum, Insecta, is distinguished by the following characteristics: Their bodies are divided into three sections, the head, the thorax and the abdomen. They have three pairs of legs that connect to the thorax.

The activity requires the class to make some value judgments about insects. Those that might be considered harmful by some people, in reality play important roles in the environment. Many of the insects provide food for fish and birds. Insects play an important role in fertilizing flowers on vegetable plants and fruit trees. Even the maggots that devour dead animals, and the beetles that chew fallen trees play an important role. On the other hand, other insects carry disease that poses a threat to human and other animal life. Some insects destroy crops.

Humankind's efforts to control insects with pesticides could have great effects on the environment. For example, DDT was used extensively to control insects before its detrimental effects on other animals were noted. Insecticide can find its way into the water supply where it can hurt animals, plants, and even insects miles away. Insecticide can enter the food chain and can be concentrated in animals at the upper end of the food pyramid, which contains animals humans eat, like fish. Also, some bugs become resistant to insecticides over time.

While many people like honey, how many of them would allow a large swarm of bees to live in their backyard? Students need to understand that insects can have both positive and negative impacts.

Links and Books


Evans, Arthur V., Charles L. Bellamy, and Lisa Charles Watson. An Inordinate Fondness for Beetles. Berkeley, California: Univ. of California Press, 2000.
Recounts the natural history as well as the human history of beetles. An authoritative reference with breathtaking photographs; newly available in paperback.

Lowenstein, Frank, and Sheryl Lechner. Bugs: Insects, Spiders, Centipedes, Millipedes and Other Closely Related Arthropods. New York: Black Dog & Leventhal Publishers Inc., 1999.
Layperson's guide to the habits and bizarre physical features of some of the most successful creatures on Earth.

Facklam, Howard, and Margery Facklam. Insects (Invaders). New York: Twenty First Century Books, 1995.
Offers an understanding of insect behavior and adaptation strategies.


"Insect Variety." Kids Discover, September 1999, 4.
Describes how no animal group better exemplifies biodiversity than insects and other arthropods.

Web Sites

NOVA Online—Japan's Secret Garden
Examines the intricate balance between humans and nature evidenced in the foothills surrounding Lake Biwa in Japan. Details how generations of farmers have transformed this land into ingeniously engineered terraces that support both rice cultivation and an abundance of wildlife. Offers additional information on this Japanese concept of "satoyama" through interviews, articles, resource links, and more.

Provides a variety of links to more information about insects.


The "Insects: Villains or Heroes?" activity aligns with the following National Science Education Standards:

Grades 5-8

Science in Personal and Social Perspectives

Science Standard F:
Science in Personal and Social Perspectives

Risks and benefits

  • Individuals can use a systematic approach to thinking critically about risks and benefits. Examples include applying probability estimates to risks and comparing them to estimated personal and social benefits.

  • Important personal and social decisions are based on perceptions of benefits and risks.

Grades 9-12

Science in Personal and Social Perspectives

Science Standard F:
Science in Personal and Social Perspectives

Natural and human-induced hazards

  • Natural and human-induced hazards present the need for humans to assess potential danger and risk. Many changes in the environment designed by humans bring benefits to society, as well as cause risks. Students should understand the costs and trade-offs of various hazards—ranging from those with minor risk to a few people to major catastrophes with major risk to many people.

Teacher's Guide
Japan's Secret Garden

Video is not required for this activity