Go Net Zero: The Climate System

Teacher Tips

Hook

• It helps to open with the question cold, “What keeps Earth warm enough for life, and what happens if that system changes?”, and take a few genuine responses before explaining anything. Most learners will have some instinct about this even without the vocabulary.
• The three images (Sunlight, Greenhouse Gases, Fossil Fuels) work best displayed together, labelled A, B and C, so shoulder pairs can refer to them directly while discussing. You might push pairs on the third question especially, “What could happen if one part of the system becomes unbalanced?”, since that’s the one that sets up the whole session.
• The written “climate system hypothesis” doesn’t need to be correct at this stage. It’s a prediction to test, not a right answer. It helps to say that explicitly, so learners aren’t afraid to commit to a guess.
• It’s worth landing the reveal clearly: the greenhouse effect is natural and keeps the planet warm enough for life. The problem is that burning fossil fuels adds extra gases, which trap more heat than the system is built for.

ITZA Pathways

• Pathway 1 (Our Fossil Fuel Fixation) covers the physical story: how fossil fuels formed, why they’re so energy-dense, and what burning them releases. Pathway 2 (The Consequences of Climate Change) covers what that’s already doing: a disrupted carbon cycle, and species like penguins whose breeding cycles are visibly breaking down.
• A good circulation question for this session is “How does something that took 300 million years to form get burned through in 200?” It’s a good way to check the scale of the timeline is actually landing, not just the vocabulary.
• If a learner pushes back with “but we need fossil fuels for everything”, that’s not a wrong instinct. It’s the exact tension the session is building toward.

Classroom Activity

• Learners copy four headings into their notebooks (Me, School, National, Global) and map how climate change shows up at each level, using what they’ve learned from both ITZA pathways. The example prompts for each level are on the slides, so there’s nothing extra to prep.
• The task asks for four specific impacts under each heading, not one or two. Four makes learners go past the first obvious answer, like melting ice for Global.
• In the second stage, learners pick one impact per category and say why. Groups can be tempted to skip straight to reading out their four lists, so it helps to hold them to the choosing and justifying.
• When you bring the class back together, you could ask for at least one example from each of the four levels, rather than whichever hands go up first. Hearing all four, from me to the world, is what ties it together.
• Early finishers can trace one of their four choices as a chain: cause, impact, consequence.

Plenary

• Part 2’s reflective question is different from the Big Question this time. It asks which part of the fossil fuel transition learners think is hardest to achieve in the real world, and why. You can push for a specific answer (jobs, infrastructure, cost, political will) rather than a vague “it’s all hard”.
• The lock-in is from Bill Gates, co-founder of Microsoft and author of a book on climate change. It pictures the atmosphere as a bathtub that keeps filling even if you turn the tap down, and only stops overflowing once you turn it off completely. It’s worth pairing with the point that follows it on the slide: reaching net zero isn’t about undoing past damage overnight, it’s about turning off the tap so the system can find balance again.
• Close by holding both truths at once: the dependence on fossil fuels runs deep, and the transition away from them is already underway. You may see learners tipping into either complete hopelessness or uncritical “technology will just fix it” optimism. Both miss the point the session is making.
• Learner journal tip: it helps if each learner makes their own copy of the journal at the start of the course and saves it somewhere they’ll find again, such as a folder on their laptop or in their school drive. It carries across every session, so if the plenary runs short, they can finish later sections for homework without losing earlier reflections.