Grade 8 Science
Explore matter, energy, and life at a deeper level.
Unit Outline
Ecology — Ecosystems, Populations & Human Impact
We are learning about ecosystem structure, food webs and energy transfer, population dynamics, and how human activity impacts the natural world.
Your Learning Journey
Assessment Criteria
All MYP Science assessments are marked against four criteria (A–D), each scored 1–8. Here is what each level looks like.
Knowing and Understanding
Explain scientific knowledge and apply it to solve problems.
Recalls some scientific knowledge with limited understanding.
Applies scientific knowledge to solve straightforward problems.
Applies scientific knowledge accurately and analyses information.
Applies scientific knowledge with precision, analysing and evaluating in unfamiliar contexts.
Inquiring and Designing
Design scientific investigations including variables, method, and safety.
States a basic problem or question. Identifies some variables.
Outlines a testable hypothesis. Designs a method with some detail.
Formulates a clear hypothesis. Designs a logical, detailed, safe method.
Formulates a precise, justified hypothesis. Designs a highly detailed, replicable investigation.
Processing and Evaluating
Collect, process, and interpret data. Evaluate the method and results.
Collects some data. Makes basic observations.
Processes data into tables/graphs. Identifies basic patterns.
Processes data accurately. Interprets trends and evaluates the method.
Processes data precisely. Draws justified conclusions and critically evaluates reliability.
Reflecting on the Impacts of Science
Discuss the implications of science on people and the environment.
States a basic connection between science and society.
Describes how science is applied and discusses an implication.
Explains the connections between science, society, and ethics with examples.
Critically evaluates the implications of science, considering multiple perspectives and ethical issues.
Lesson Slides
Worksheets
Review Games
Videos
Key Vocabulary
Essential terms for this unit. Use these to build your scientific vocabulary.
Ecosystems & Food Webs
All living organisms and non-living factors in an area, interacting together.
Living factors: predators, prey, competition, disease, food availability.
Non-living factors: temperature, light, water, soil pH, wind.
Makes its own food by photosynthesis. The base of every food chain.
Gets energy by eating other organisms. Primary, secondary, tertiary.
Breaks down dead matter, recycling nutrients back to the soil.
A feeding level. Energy decreases at each level (~10% passes on).
Interconnected food chains showing all feeding relationships in an ecosystem.
Populations & Human Impact
All individuals of one species in an area.
All populations of different species living in the same area.
The variety of living organisms. High biodiversity = stable, resilient ecosystem.
A species at risk of extinction due to habitat loss, hunting, or climate change.
Clearing forests for farming or development. Reduces biodiversity and increases CO₂.
Protecting ecosystems and species through management, reserves, and sustainable practices.
🚀 Extension Activities
Go beyond the textbook. Choose an activity that interests you and challenge yourself.
Conservation Campaign
Persuasive ProjectChoose an endangered ecosystem: the Yangtze River, Korean DMZ, or Germany's Wadden Sea. Create a persuasive campaign (poster, video, or presentation) arguing why it must be protected. Include scientific data, not just emotional appeal.
NIS Food Web Map
Field InvestigationSpend 30 minutes observing organisms in the NIS school grounds. Identify as many species as you can. Construct a food web showing the feeding relationships. Where are the producers? Consumers? Decomposers? What would happen if you removed one species?
Yangtze Fishing Ban Data Analyst
Data & PredictionResearch the data from China's 10-year Yangtze fishing ban (started 2021). Has fish population recovered? Have any species returned? Use the available data to create graphs showing trends and predict what the ecosystem might look like in 2031.
Carbon Footprint Calculator
Maths & Science ExtensionCalculate your personal carbon footprint for one week. Include: transport to school, electricity at home, food choices. Compare with the average in China, South Korea, and Germany. What single change would reduce your footprint the most?
Explore
Interactive simulations and tools. Use these to deepen your understanding.
10% Rule Calculator
Mr ZocchiEnter producer energy — see the 10% rule across trophic levels.
Natural Selection
PhET SimulationSee how populations change over time based on environmental pressures. Add predators, food changes, and mutations.
Ecosystem Explorer
National GeographicExplore different ecosystems around the world and their biodiversity.
↗ Open ToolDesmos Scientific Calculator
DesmosCalculate population changes and energy transfer percentages.
↗ Open ToolFood Web Simulator
Mr ZocchiRemove organisms from a Yangtze River food web and observe cascade effects on every trophic level.
Self-Quiz
Click a question to reveal the answer.
What is the difference between biotic and abiotic factors?
Biotic = living (predators, prey, disease). Abiotic = non-living (temperature, water, light, soil).
Why do food chains rarely have more than 4-5 trophic levels?
Only ~10% of energy passes to the next level (rest lost as heat through respiration). By level 5, there's barely any energy left.
A pesticide kills insects in a food web. Predict what happens to the bird population.
Bird population decreases — their food source (insects) has been removed. Knock-on effects ripple through the web.
What are three human activities that reduce biodiversity?
Deforestation, pollution (air/water/soil), overfishing, urbanisation, introduction of invasive species, climate change.
Why are decomposers essential?
They recycle nutrients from dead organisms back into the soil, making them available for plants. Without them, nutrients get locked in dead matter.
What is the 10% rule?
Only about 10% of energy at one trophic level is passed to the next. The rest is used for life processes or lost as heat.
What is a keystone species?
A species that has a disproportionately large impact on its ecosystem. Removing it causes major changes (e.g. wolves in Yellowstone).
Explain why removing one species can affect the whole ecosystem.
Organisms are interconnected through food webs. Removing one affects its predators (less food) and prey (population explosion), causing a cascade.
Common mistake: 'Decomposers are not important.' Why is this completely wrong?
Without decomposers, dead matter piles up, nutrients are locked away, soil becomes infertile, plants die, and the entire ecosystem collapses.
How does deforestation in one country affect the whole planet?
Trees absorb CO₂. Fewer trees = more CO₂ = enhanced greenhouse effect = global climate change. Also reduces biodiversity globally.
What is the difference between conservation and preservation?
Conservation: sustainable management and use. Preservation: protecting an area from ALL human activity.