Print Friendly, PDF & Email


SUBJECTS — The Environment;



AGE:  Rated PG, age 9+;

2020; 1 hour 23 minutes; Color.

Give your students an image that could change their lives.  Check outThe Sealed Petri Dish  Assignment!

In this Learning Guide citations to Mr. Attenborough’s book, A Life on Our Planet – My Witness Statement and a Vision for the  Future, written with Jonnie Hughes, will be to “Attenborough” with a page reference.

Print Friendly, PDF & Email



TWM offers a worksheet for students to review before seeing the film and then to fill out after they have watched the movie. While not required for the lesson plan, teachers may want to review it. See Film Study Worksheet for a Documentary Seeking to Persuade the Viewer On a Matter of Political or Social Significance.


This film is one man’s witness statement about the degradation of the world’s environment over his lifetime. Mr. Attenborough ends the film with a message of hope that with human birth rates going down all over the world we’ll be able to establish a modern sustainable ecological balance halting the progress of the Sixth Mass Extinction.



David Attenborough and Max Hughes;


Alastair Fothergill, Jonathan Hughes;


Three award nominations: BAFTA Awards 2021: nominated for Best Documentary; 2021 ASCAP Film and Television Music Awards: nominated for Documentary Score of the year; and Cinema Audio Society, USA 2021: nominated for Outstanding Achievement in Sound Mixing for Motion Pictures – Documentary


This film poses questions that citizens must answer about the most serious and pressing existential threat to humankind.




Watch the film with your children. Read magazine articles or books, or watch other films about the environmental crisis. Try Fly Away Home (ages 10+) and Cowspiracy: The Sustainability Secret (ages 13+).  Then talk about ways to help reduce environmental degradation in your lives. Mr. Attenborough’s book, A Life on our Planet, is excellent reading for high level high school and up.


Mr. Attenborough describes this film as his “witness statement.” He is referring to the tradition in (1) religion, (2) in support of movements for social reform, or (3) in the presence of great evil, of people stating an important but perhaps unwanted truth. It is sometimes called “bearing witness.”   An example of (1) occurs in the New Testament when Jesus tells his disciples to bear witness about him and their faith. See e.g., Acts 22:15 and 23:11.  Examples combining (2) and (3), occurred on many occasions before the Civil War in the U.S. when Abolitionists would bear witness to the evils of slavery and the need for reform, calling attention to the nation’s “original sin” through public prayer services and vigils.  An example of (3), bearing witness to great evil, occurred at the end of WW II in Germany.  General Eisenhower, Commander of the Allied Forces in Europe, upon discovering the horrific Nazi death camps said, “For the dead and the living, we must bear witness.” Even today, Animal Rights activists feed water to pigs crammed together in the large trucks used to transport them to slaughter both to relieve the pigs of a little of their suffering and to bear witness to that suffering.


Chernobyl Nuclear Accident

In April 1986 a reactor at the Chernobyl nuclear power plant in Ukraine went into an uncontrolled nuclear chain reaction and exploded. The accident was due to a flawed Soviet reactor design and serious errors by operators acting in a work environment that lacked a strong safety culture. It was the worst nuclear disaster in history. At least 5% of the radioactive reactor core was ejected into the environment. Thirty firefighters and other first responders died of acute radiation exposure and 300,000 people had to be evacuated from surrounding areas. While most of the radioactive debris was deposited locally, some was carried by air currents to many parts of Europe. Clean-up efforts are ongoing and are not expected to be completed until 2065.



Bearing Witness — to make a statement acknowledging that something exists or is true; often it refers to stating what other people need to hear but what they don’t want to hear.


Holocene – “A geological epoch, beginning about 11,700 years ago after the last glacial period.  It has been a strikingly stable period of [geological] history, and corresponds with a rapid growth in humankind brought about by the invention of agriculture.”  Attenborough, A Life on Our Planet, p. 231  It is the accepted term for the present epoch, which is the second epoch in the Quaternary period and followed the Pleistocene.


Anthropocene – “A proposed geological age, or more technically, epoch, viewed as the period during which human activity has been the dominant influence on climate and environment. There is an ongoing debate as to when the Anthropocene would begin, but many suggest the 1950s since it will coincide with the presence in future rocks of an abundance of plastics and radioactive isotopes from nuclear testing.” Attenborough, A Life on Our Planet, pp. 223 & 224.


Biodiversity — the variety of life on Earth at all its levels, from genes to ecosystems  It encompasses the evolutionary, ecological, and cultural processes that sustain life.


Mass Extinction — a loss of three-quarters or more of all species in existence across the entire Earth over a “short” geological

period of fewer than 2.8 million years. There have been five previous mass extinctions; we appear to be at the beginning of the sixth.  Mr. Attenborough in his book explains the meaning of mass extinction as follows:

For different reasons  at different times in the Earth’s history, there had been a profound, rapid, global change to the environment to which so many species had  become so exquisitely adapted. The Earth’s life–support machine had stuttered and the miraculous assemblage of fragile interconnections which held it together had collapsed. Great numbers of species suddenly disappeared leaving only a few.  Attenborough, A Life on Our Planet, p. 16.

He comments that all the evolution that led to the extinct species was undone  by the five great extinctions.


Rewild – To allow a geographic area the has been disrupted by human activity to return to its natural state.


Chart of World Population, Atmospheric Carbon, and Remaining Wilderness

Below is a chart taken from Mr. Attenborough’s book, A Life on Our Planet – My Witness Statement and a Vision for the Future.  A few of these entries are shown in the film.  The chart can be printed and given to the class before and briefly reviewed before they see the film.  For a pdf file containing the chart, click here.


1937:  World population: 2.3 billion; Carbon in atmosphere: 280 ppm; Remaining wilderness: 66%

1954  (+17 years): World population: 2.7 billion; Carbon in atmosphere: 310 ppm; Remaining wilderness: 64%

1960  (+16 years) World population: 3.0 billion; Carbon in atmosphere: 315 ppm; Remaining wilderness: 62%

1968  (+8 years) World population: 3.5 billion; Carbon in atmosphere: 323 ppm; Remaining wilderness: 59%

1971 (+3 years) World population: 3.7 billion;  Carbon in atmosphere: 326 ppm;  Remaining wilderness: 58%

1978 (+5 years) World population: 4.3 billion; Carbon in atmosphere: 335 ppm; Remaining wilderness: 55%

1989  (+11 years); World population: 5.1 billion; Carbon in atmosphere: 353 ppm; Remaining wilderness: 49%

1997  (+8 years) World population: 5.9 billion; Carbon in atmosphere: 360 ppm; Remaining wilderness: 46%

2011  (+4 years) World population: 7.0 billion; Carbon in atmosphere: 391 ppm; Remaining wilderness: 39%

2020   (+9 years)World population: 7.8 billion; Carbon in atmosphere: 415 ppm;  Remaining wilderness: 35%


Text of the short subject entitled “How to Save Our Planet” from the David Attenborough website.


Suddenly, saving our planet is within reach. We’ve worked out all the problems. We’re working on all the solutions. Most of them we can do now. And over time all of them help the economy. Our population growth is actually slowing down and by the end of the century, it will plateau. There’s never been a better opportunity to take control. The plan is obvious. Stop doing the damaging stuff. Roll out the new green tech systems as they arrive. Stabilize the human population as low as we fairly can. Keep hold of the natural wealth we’ve currently got. And in 80 years’ time, we’ll be past the worst of it.

More than that we’ll have built a world with eternal energy, clean air, and water. A stable, healthy world that we can benefit from, forever.

So, what’s stopping us? This opportunity is out of sight. Each of us is blinkered by the demands of here and now. “Big picture.” “long term,” they’re not in our field of vision. That must change if we’re going to change.

We now have the choice to create a planet that we can all be proud of. Our planet: the perfect home for ourselves and the rest of life on earth;

We have a plan. We know what to do. There is a path to sustainability. If enough people can see the path, we may just start down it in time.


The website for the film David Attenborough: A Life on Our Planet has the following short subjects that might be helpful in presenting the issues raised by the film.

How to Save our Planet 8:07;

Five Steps to Help Save Our Planet 25 seconds;

A Reason for Hope 2:45;

Our Changing Planet 1:05;

How to Save our High Seas 8:27;

How to Save our Grasslands 8:36; and

How to Save Our Jungles 8:24.


Acquaint the class with the important concept of “bearing witness” and its role in social change. See Helpful Background.


The Five Steps to Help Save Our Planet outlined by Mr. Attenborough are:

1. Make your diet as plant-based as possible;
2. Shop for sustainable fish and meat;
3. Switch to a clean energy provider;
4. Choose deforestation-free palm oil products; and
5. Buy wood and paper from well-managed forests.

The Sealed Petri Dish Assignment

Have the class read the following section from Mr. Attenborough’s book A Life on Our Planet and then write a one-page essay about how the situation of human beings on earth is similar to and different from the bacteria in the petri dish.  When the assignments have been graded have the authors of the best read their essays to the class.  Then conduct a class discussion on the topic.

When a few bacteria are placed on a bed of food in a sterile, sealed dish —  a perfect environment free from competition, sitting on abundant nutrients  — they take some time to adapt themselves to the new medium  — a period called the lag phase.  This can last just one hour, or a few days, but at some point it ends suddenly —  the bacteria solve the problem of how to exploit the conditions of the dish, and begin to reproduce by dividing, doubling their population as frequently as every 20 minutes. So begins the log phase, a period of exponential growth, the bacteria splitting and spreading and surges across the surface of the food.  Each individual bacterium grabs its own plot and seizes is what it needs. Ecologists called this a scramble competition – every bacterium for itself!  It’s a type of competition that does not end well in a closed system such as the finite, sealed dish. When the bacteria reproduce to such a degree that they reach the edge, every individual cell will begin to disadvantage every other at the same moment. The food begins to run out beneath the bacteria. Exhaust gases, heat and effluents begin to accumulate and poison with increasing speed.  Cells start to die tempering the growth rate of the population for the first time. These deaths also occur exponentially due to the worsening environment, and soon there is a moment when the death rate and the birth rate equal each other at that point the population has peaked, and may plateau for a period. But within a finite system this won’t continue forever — it’s not sustainable.  Food starts to run out everywhere, the gathering waste becomes deadly throughout the dish and the colony crashes as quickly as it rose. Ultimately, the seal dish becomes a very different place – a place with no food, it’s environment ruined, hot, acid and toxic.  David Attenborough, A Life on Our Planet, pages 106 & 107.

Good discussions will cover the following points:  1) The earth has various biochemical cycles that cleanse and replenish the environment.  The carbon cycle and the oxygen-carbon dioxide cycle are two of the most important.  However, our overpopulation and interference in the environment is disrupting these beneficial cycles.  For example, over the last three hundred years, human beings have introduced massive amounts of carbon dioxide into the atmosphere by burning

fossil fuels such as wood, coal, oil, and natural gas, thus disrupting the carbon cycle. This has contributed to global warming, acidification of the oceans, and other environmental problems.  Our increasing population and continuing interference with the natural cycles of the earth bring the world ever closer to the petri dish experiment.  2) People have intelligence and technology.  If we really care about saving our civilization and other animals we can use our ingenuity to adjust our impact on the sealed environment of the earth and its atmosphere.  We already employ technology to make our lives more comfortable and to increase the number of people who can live on the planet.   Examples are all around us.  We have systems to bring food to our cities and to remove sewage.  Without them we would starve or be awash in our own effluents.  What we need to do is to apply our inventiveness to restoring the natural cycles of the earth.  3)  Similarities between the world and the sealed petri dish are that: we are all alive (bacteria and human beings); in the process of living we create waste products that are toxic to us and harmful to the environment; we share the inability to control our populations; neither bacteria nor homo sapiens can our greed in grabbing more than our share of the available resources.

Before the end of the time allotted for this exercise, lead the class to discuss what human beings can do to avoid the fate of the bacteria in their sealed petri dish.   Teachers seeking to further explore these issues, can have students investigate the Gaia Hypothesis and Gaia 2.0.    A suggested essay prompt: What does the Gaia Hypothesis tell us about how to avoid the fate of the bacteria in the petri dish experiment?

Print Friendly, PDF & Email


1. [Before asking this question show the class the 25-second video on the movie’s website called: Five Steps to Help Save Our Planet.] Mr. Attenborough has Five Steps to Help Save Our Planet. The first step is to “Make your diet as plant-based as possible.” Why does he say this?

Suggested Response:

This topic is more fully explored in the Learning Guide to Cowspiracy: The Sustainability Secret, but in short, animal agriculture (production of meat and dairy) is responsible for more pollution than the entire transportation sector. The crops necessary to feed those animals consume more than 50% of the potable water in the U.S.  One hamburger with 1/3rd of a pound of beef requires 660 gallons of water to produce. The deforestation of the Amazon is primarily to grow crops to feed livestock. The grazing land necessary to produce meat is a major cause of deforestation all over the globe.  The pollution caused by the many hundred million tons of animal waste generated for the production of meat and dairy each year is immense. Methane gas from the digestive tracts of cows (yes, cow farts) is a more long-lasting and potent greenhouse gas than carbon dioxide.


2. Do people have a right to have as many children as they please – even if the numbers of our population are destroying the world ecosystem?

Suggested Response:

Students will disagree. The goal is to raise the issue and have a respectful airing of differing views.   Many people consider  having children to be a fundamental right and believe that having as many children as they desire is part of that right.   The argument against this view is that (1) rights are granted by society and what is a fundamental right in one society  may be a crime in another society; and (2) having more than 2 or 3 children is destructive to the environment and harms everyone.


3. What is the quickest and best thing that you can do to help protect the oceans?

Suggested Response:

The best thing to do is to stop eating any wild-caught fish, including canned fish. Reduced demand means fewer fishing boats and fewer lost nets and lines in which aquatic animals can become entangled.


4. What is your plan for how human beings are going to save the planetary ecosystem and how are you going to contribute to that effort?

Suggested Response:

The point of this question is that given the current situation everyone will need to have an idea of what they want for the planet in the future and how society can attain the goal of a balanced sustainable ecosystem.   As Mr. Attenborough points out, our actions should be lead to a balanced sustainable world.   As this Learning Guide is written, very few people, students or adults, have such a plan, but it is something we should all be thinking about.  Not everyone will be able to develop a comprehensive plan, but certainly we should be thinking about how we can change our lives to reduce our ecological footprint.  If we all contribute to the effort, the change will be enormous.


5. We are all guilty of participating in the environmental degradation that is destroying our world. Describe some actions that we can all take to reduce that guilt.

Suggested Response:

Students will have many good ideas.  Examples are:

Become an environmental activist;

Restrict our consumption of meat and dairy;

Sell one of the family’s automobiles.


6. What can you say to a person from a poor developing country who wants to live the rich and environmentally destructive life-style now enjoyed by many affluent people in the U.S.?

Suggested Response:

There is no one correct response. The idea is to get the class thinking. Here are some thoughts.

We’d be in a much better position to talk to a person from a developing country about safeguarding the environment if: 1) we had reduced our own consumption and 2) our country or we ourselves had personally assisted them in attaining sustainable development in their country.


7. So, what’s stopping you from doing something to help the environment and to preserve humanity and the non-human animals at risk from climate change?

Suggested Response:

There are many reasons. The bias toward normalcy is a big factor.  In addition, as Mr. Attenborough tells us, the problem is often out of sight and we are blinkered by the demands of here and now.   These are “big picture” “long term” problems and it is easy to put them our of our minds.  That must change if we’re going to change.


8.  What is “cultured meat” and why does Mr. Attenborough call it “clean meet”?

Suggested Response:

For Attenborough’s reference to this, see A Life on Our Planet p. 226.  Cultured meat, also called clean meat, is “Meat for consumption produced as a cell culture of animal cells rather than from the slaughter of animals. It is a form of cellular agriculture. Research suggests that clean meat production has the potential to be much more efficient and environmentally friendly than traditional meat production, as it requires a fraction of the land, energy needs and water, and emits far fewer greenhouse gases per kilogram produced. It also has fewer animal welfare issues.”


Social-Emotional Learning Here.


Moral-Ethical Here.


TWM recommends The Petri Dish Assignment, above.  In addition, many of the discussion questions can be the subject of an essay. Students can be assigned to research and write essays on the current state of different parts of the environmental collapse and how that might affect our lives.  Examples include:

• the loss of the ice-caps of at the North and South Poles;
• the destruction of the Amazonian and other rain forests;
• the over-fishing of the seas;
• the acidification of the Oceans;
• the threat caused by methane emissions from factory farming and the melting of the permafrost;


Students who are interested in expressing themselves through the visual arts can create a sketch or painting inspired by the film. If there are enough interested students this project  can be turned into a competition with outside judges picking the winners.


Students can write a poem describing their reaction to the film or inspired by the film.


Multimedia: Anchor Standard #7 for Reading (for both ELA classes and for History/Social Studies, Science, and Technical Classes). (The three Anchor Standards read: “Integrate and evaluate content presented in diverse media, including visually and quantitatively as well as in words.”) CCSS pp. 35 & 60. See also Anchor Standard # 2 for ELA Speaking and Listening, CCSS pg. 48.

Reading: Anchor Standards #s 1, 2, 7 and 8 for Reading and related standards (for both ELA classes and for History/Social Studies, Science, and Technical Classes). CCSS pp. 35 & 60.

Writing: Anchor Standards #s 1 – 5 and 7- 10 for Writing and related standards (for both ELA classes and for History/Social Studies, Science, and Technical Classes). CCSS pp. 41 & 63.

Speaking and Listening: Anchor Standards #s 1 – 3 (for ELA classes). CCSS pg. 48.

Not all assignments reach all Anchor Standards. Teachers are encouraged to review the specific standards to make sure that over the term all standards are met.


The following books are recommended for excellent high school level readers.






Bearing Witness:


Chernobyl Explosion:


The books listed in the Bridges to Reading section.

This Learning Guide was written by James A. Frieden. It was published on April 18, 2021 and updated on May 22, 2021.

Print Friendly, PDF & Email


TWM offers a worksheet for students to review before seeing the film and then to fill out after they have watched the movie. While not required for the lesson plan, teachers may want to review it. See Film Study Worksheet for a Documentary Seeking to Persuade the Viewer On a Matter of Political or Social Significance.



  • For other films relating to the environment, click here.


  • For a movie describing some unexpected ways in which non-human animals have temporarily improved their lives during the Covid-19 Pandemic shutdowns, see The Year the Earth Changed.


  • For a 2019 eight-part series — each segment about 54 minutes — by David Attenborough celebrating the natural wonders that remain and revealing what we must do to preserve them and to ensure that people and nature thrive, go to Our Planet.

Search Lesson Plans for Movies

Get our FREE Newsletter!

* we respect your privacy. no spam here!

Follow us on social media!