4.4.4.2 Germs
Recognize that the body has defense systems against germs, including tears, saliva, skin and blood.
Give examples of diseases that can be prevented by vaccination.
Overview
MN Standard in Lay Terms
Germs and other microorganisms can make you sick. Your body can defend itself against germs and other microorganisms.
Big Idea
People need to be aware of how germs and other microorganisms can affect them so that they can stay healthy. The body is able to protect itself against many diseases.
MN Standard Benchmarks
4.4.4.2.1 Recognize that the body has defense systems against germs, including tears, saliva, skin and blood.
4.4.4.2.2 Give examples of diseases that can be prevented by vaccination.
The Essentials
Gary Larson- The Far Side -
- NSES Standard
Standard F: As a result of activities in grades K-4, all students should develop understanding of personal health...
Individuals have some responsibility for their own health. Students should engage in personal care-dental hygiene, cleanliness, and exercise-that will maintain and improve health. Understandings include how communicable diseases, such as colds, are transmitted and some of the body's defense mechanisms that prevent or overcome illness.
- AAAS Atlas:
There are some diseases that human beings can catch only once. After they've recovered, they don't get sick from them again. There are many diseases that can be prevented by injecting people with killed or weakened germs so that people don't catch the diseases even once. 6E/E4 (ID: SMS-BMK-0391)
(K-2) Some diseases are caused by germs, some are not. Diseases caused by germs may be spread by people who have them. Washing one's hands with soap and water reduces the number of germs that can get into the body or that can be passed on to other people. 6E/P3 (ID: SMS-BMK-0387)
Some germs may keep the body from working properly. For defense against germs, the human body has tears, saliva, and skin to prevent many germs from getting into the body and special cells to fight germs that do get into the body. 6E
- Common Core Standards
Common Core Standards (i.e. connections with Math, Social Studies or Language Arts Standards):
Language Arts:
4.2.5.5 Describe the overall structure (e.g., chronology, comparison, cause/effect, problem/solution) of events, ideas, concepts, or information in a text or part of a text.
4.2.7.7 Interpret information presented visually, orally, or quantitatively (e.g., in charts, graphs, diagrams, time lines, animations, or interactive elements on Web pages) and explain how the information contributes to an understanding of the text in which it appears.
Misconceptions
from national science digital library:
- Elementary-school students may have the following ideas about germs: Germs are microorganisms causing illness; germs enter the body through the mouth while eating and leave the body through the mouth; every illness is caused by germs; all diseases are caused by the same kind of germ; the process of infection is automatic; any infection in the body necessarily makes it ill; and when medicine is administered, healing takes place immediately. [1]
- Lower elementary-school children may think that illness is the result of misbehavior and realize that they are ill only when they are told that they are by others or when their illness has a behavioral impact, such as having to stay in bed or to go to the doctor. Upper elementary-school children may believe that all illnesses are caused by germs and are contagious. As students grow older, their beliefs about causes of illness begin to include also the malfunctioning of internal organs and systems, poor health habits, and genetics. Upper elementary students can understand that a change in internal body state or the experience of symptoms is the consequence of illness. [2]
[1] Nagy, M.H. (1953). The representations of "germs" by children. Journal of Genetic Psychology, 83, 227-240.
[2] Hergenrather, J., Rabinowitz, M. (1991). Age-related differences in the organization of children's knowledge of illness. Developmental Psychology, 27, 952-959.
Vignette
It's January in Mrs. Amoeba's 4th grade class, Zong asks "Mrs. Amoeba why are so many classmates out sick?" Mrs. Amoeba realizes its time to talk about germs.
First Mrs. Amoeba assess students current knowledge about germs. She uses her Smart Board to collect what students already know about germs and microorganisms. Mrs. Amoeba quickly realizes a few things:
- Students think all microorganisms are bad
- Students don't realize they can play an active role in their own health
- Students think that germs only enter the body via the mouth
- Students don't know what vaccinations are
The next day Mrs. Amoeba starts her activity by having students shake hands "now what did you just share with your partner?" Mrs. Amoeba fields answers until she gets the conversations started around gems. Students make a list of questions they have about germs and the class decides to complete a germ research project. Students use the website to learn more about germs. Once their questions are answered they create a web of their ideas using Inspiration or webspiration (if technology is unavailable students can just draw this):
Students now take what they have learned about germs and use Comic Life (software) or toondo.com (free website) to create a comic about germs (alternately if technology is not available students can do this on paper). Mrs. Amoeba gives the students specific instructions that the cartoon must be about: types of germs or the way the body protects itself from germs or the important times to wash your hands. Mrs. Amoeba uses the cartoon as the assessment; she looks for scientific accuracy and an understanding of science concepts about germs, the body's defense against germs and the importance of hand washing.
Resources
Suggested Labs and Activities
4.4.4.2.1 Germs and The Body
The purpose of this activity is to illustrate where germs exist, how they can get into and affect the body, and how the body defends itself against them.
Glogerm activity:
1. Have students turn to partner and give a High 5. Tell them to look at their hands.
Their partner just gave them something. What is it? Germs!
2. Discuss how some germs are bad.
3. Introduce Glogel. Tell them that is not real germs and it will not hurt. Then go around and give each child some Glogel
5. Turn off the lights. Go around and show the students their hands under the Black light.
6. Divide the class into thirds for the experiment. Have a third use Hand Sanitizer to clean their hands, a third rinsing their hands with plain water, and a third washing their hands with soap and water.
7. Inspect hands with the black light. Compare one student from each group, placing their hands side-by-side under the light. Discuss which one worked the best to clean their hands (soap and water).
The best way to clean your hands is to use soap and water. Teach the procedure for proper hand washing.
Glogerm can be purchased from many science supply chains such as Carolina Biological.
Instructional suggestions/options
- A hands on activity like Glogerm is classic, it can also be simulated using glitter if Glogerm is not available. Another method for using Glogerm is to put some on a used space in the morning like the door handle or the water fountain, and then use the light to see where the glogerm has spread
- Growing bacteria cultures is an unsafe practice for elementary schools
Vocabulary/Glossary:
(Many definitions are modified from this site - a good resource for science definitions)
- Microorganism- A microscopic organism, including bacteria, protozoans, yeast, viruses, and algae.
- Microbes are single-cell organisms so tiny that millions can fit into the eye of a needle. They are the oldest form of life on earth.
- Germ- General designation for a microorganism. an infectious agent
- Virus- is a small infectious agent that can replicate only inside the living cells of organisms. Most viruses are too small to be seen directly with a light microscope.
- Vaccination- Inoculation of viral or bacterial organisms or antigens to produce immunity in the recipient. (not a 4th grade definition)
- body defense system
- tears- a watery fluid continually secreted by the eye, serving to moisten and protect the eye and keep it clear of foreign particles.
- saliva- a watery fluid in the mouth that functions in the tasting, chewing, and swallowing of food.
- skin- the soft external covering of a human or animal body, serves to protect the body
- blood- the fluid that circulates in human beings and other animals, caring nutrients and oxygen to all parts of the body.
- disease- a disordered or incorrectly functioning organ, part, structure, or system of the body resulting from the effect of genetic or developmental errors, infection, poisons, nutritional deficiency or imbalance, toxicity, or unfavorable environmental factors; illness; sickness; ailment. See this reference.
- prevention- the act of preventing or stopping something from happening
Websites:
- Here is a tour of human body systems in English and Spanish (not specific to this standard, but good background info)
- This site includes the computer activity- bacteria in the cafeteria- a great intro to helpful and harmful bacteria
- Tissues of life (Science Museum of Minnesota) - good resource for learning about human skin
- Glogerm activity: video of Glogerm activity - from dragonfly TV
Social Studies: Have classes look at how diseases spread around the world throughout history: the Spanish influenza and the bubonic plague and today swine flu and the Haiti Cholera Epidemic
Additional resources
- tour of human body systems in English and Spanish (not specific to this standard, but good background info)
- includes the computer activity- bacteria in the cafeteria- a great intro to helpful and harmful bacteria
- Tissues of life (Science Museum of Minnesota) good resource for learning about human skin
- Glogerm activity: video of Glogerm activity- from dragonfly TV
- Toondoo- like comic life but free
- Microbworld: excellent introduction to microbes (Um... pic of beer on home page?)
Assessment
Assessment of Students
Include questions designed to probe student understanding of concepts, both formative and summative. Identify taxonomic level of questions.
Catching a Cold (Uncovering Student Ideas in Science Volume 4 p. 125)
Six assessment questions here:
1. What are germs (short answer Level 1- recall):
a. An infections microorganism that can make you sick.
2. All of the following are types of germs except (short answer Level 1- recall):
a. Protozoa
b. bacteria
c. fungi
d. white blood cells
e. viruses
3. The common cold is spreading through your school, the student council is recommending that everyone get vaccinate against the flu to stop the spread of this cold virus, tell me whats wrong with their thinking (Level 3 analysis)?
a. the answer should reflect germ theory- how people catch colds from germs, the answer should also note that the flu and the common cold are two different illnesses and there is no vaccination against the common cold.
4. Please select which of the following are ways you can catch a cold :
a. being cold and wet
b. germs
c. leaving the window open while sleeping
d. staying indoors and not getting enough fresh air
5. List one function of the body that protects it from germs and how (level 2 ):
a. some examples are:
i.skin
ii.tears
iii.saliva
iv.blood
6. Give an example of a disease that you can be vaccinated against:
a. some examples are
i.the flu
ii.polio
iii.hepatitis
iv.measles
v.mumps
vi.diphtheria
Assessment of Teachers
Catching a Cold (Uncovering Student Ideas in Science Volume 4 p. 125)
Teachers should reflect on the following before teaching this unit: what do I already know about germs and germ theory? What misconceptions do I have about germs and illness? What do I need to know about germs and germ theory to accurately teach this information to students?
What can I do to stay healthy?
Differentiation
Struggling and At-Risk
Bricks and mortar vocabulary labels and word walls, vocabulary posters, pre-teaching: accessing prior knowledge, graphic organizers, each activity needs to have reading, writing, speaking, listening component. (Keenan) This site offers a "read the website option"
Bricks and mortar vocabulary labels and word walls, vocabulary posters, pre-teaching: accessing prior knowledge, graphic organizers, each activity needs to have reading, writing, speaking, listening component. (Keenan) This site offers a "read the website option"
Provide a scaffolding for students to do an independent research project about a disease that can be prevented by a vaccination, or the history of vaccination or on Doctor Edward Jenner (1749-1823) or Jonas Salk.
Current events discussions around diseases that are no longer found in the US like small pox and polio that still occur and why are good conversations to start, the teachers focus should be on helping students understand our (people) role in the health of populations role around the world.
Bricks and mortar vocabulary (bricks are content specific vocabulary like germ and bacteria. Mortar are words that a student might need but are not content- for this unit examples might be- function or system) labels and word walls, vocabulary posters, pre-teaching: accessing prior knowledge, graphic organizers, each activity needs to have reading, writing, speaking, listening component. (Keenan) This site offers a "read the website option"
Parents/Admin
Administrators
Teachers should not use terms like germs and microbes or bacteria interchangeably. Although germs can be bad for our health many types of microbes and bacteria are essential to life, teachers should be careful to make this clear for young students. Teachers should be explicit in teaching that germs can enter the body in many ways and what defenses the body has against germs.
Students and parents can go on a scavenger hunt around the house looking for locations that might have the most germs and why. for example- the doorhandles and the telephone because everyone touches it, or the toy box because lots of neighborhood kids play with the toys. Families can then work together to give these locations an extra good cleaning.