Bell ringer: start here (while attendance happens)
Prior-knowledge probe · 5 min

From last class: what factors did you list as making a planet habitable? Add one more factor now that you've slept on it.
Task: Share with a partner.

Answer in your Field Notebook, dated.

Today we are learning

I can name Earth's four subsystems (atmosphere, hydrosphere, geosphere, biosphere) and give a concrete example of how two of them interact.

I can: tick as you go (for you, not for marks)
full course map →
AI Partners available for today's work
Remember: every AI use gets documented. → AI Documentation Template

What today is about

Last class: a list of factors. Today: a system.

In Block 1 you listed five-plus factors that might affect whether a planet can support life. Today we make the move that the rest of this course depends on: those factors don't sit alone. They interact. A magnetic field protects an atmosphere. An atmosphere holds heat and shapes water cycles. Water shapes weather, weather shapes rocks, rocks shape carbon storage. Earth's habitability isn't a checklist; it's a system.

The right unit of analysis from here on is Earth's four subsystems: the atmosphere (air), hydrosphere (water), geosphere (rock + interior), and biosphere (life). Each one interacts with the others through energy flows and matter cycles, and many of those interactions are feedback loops: relationships that either amplify a change (positive feedback) or push back toward stability (negative feedback). Systems thinking is the lens you'll use for every unit after this one too: weather, plate tectonics, hydrology, ecology, energy, sustainability. It all comes back to this move.

The Systems Diagrammer AI partner launches today. It's a coach, not a drawing tool; it asks you the questions you'd ask yourself if you had more practice. The goal is that by exit ticket you have a defensible first systems diagram, drawn by you.

You'll draw twice today: once your way, once the shared way. The difference between those two drawings is the point.

Before you start the work

Keep this open. The handout is provided in class and is the reference for today's diagram work. Notes go in your Class Notebook as a Power outline.

Taking notes? Power 1 seeds for today
the four spheres · feedback loops and their signs · the format
Read
Feedback Loops (Three Worked Examples) handout: ice-albedo (+), water-vapor (+), carbon-silicate thermostat (−), with the sign-test conventions you'll use in your own diagram. Printed copies in class.

Everyone does this

Earth as a Planet: decks 1 and 2
Before you draw four spheres, meet two of them properly. Deck 1 is the geosphere: layers, core, magnetic field. Deck 2 is the atmosphere, and where it came from.
Read: Life Needs Matter to Move
Read before class. Bring your three answers.
Read: Four Spheres, One System
The four subsystems and the traffic between them. This reading says it links from Block 2, and until now it did not.
Meet your new partner
The Systems Diagrammer: Socratic coach for diagram-building. Read the opening message and the example exchange before you use it in Path C below.
Positive ≠ good
In systems language, positive and negative are directions, not judgments. A positive feedback amplifies change, even harmful change. A negative feedback stabilizes. If you catch yourself thinking "positive = good," run the perturbation test instead.

Today's work: choose one path

Three real paths. All three end at the same exit ticket: a defensible first systems diagram of Earth.

Sketch first: no words

Before the convention, your picture. Five minutes, alone: draw how Earth's parts connect: your way, pictures only, no words. Then three minutes with a partner: where do your drawings agree? Keep the sketch in your Field Notebook, dated. Now, the choice board below teaches the shared way scientists draw this, and you'll feel why the conventions exist: you just hit every problem they solve.

Learning Intention: I can name Earth's four subsystems (atmosphere, hydrosphere, geosphere, biosphere) and give a concrete example of how two of them interact.
A
Diagram-first
On blank paper: sketch all four subsystems as labeled circles. Draw at least three arrows connecting them, with a verb on each arrow ("evaporates," "weathers," "absorbs"). Label one loop in your diagram as positive (+) or negative (−) and justify the sign in one sentence below.
Visual · Solo
B
Pair-walk
Pick one specific interaction with a partner; ocean ↔ atmosphere is a strong starter. Talk it through verbally: what flows from A to B, what flows back, what would happen if you removed one direction. Then both of you draw it independently and compare.
Verbal · Pair
C
AI-coached
Open the Systems Diagrammer in a new tab. Tell it you're new to systems diagrams and you want to build your first Earth one. Work through its questions: name one subsystem, then another, then an interaction. You draw on paper as you go; the partner stays Socratic. End with a feedback-loop sign question.
Conversational · Solo

Open your Class Notebook and type today's entry header as Heading 2:

A: Sep 7 | U1 B2 | Earth as Baseline: Systems Thinking + SubsystemsB: Sep 4 | U1 B2 | Earth as Baseline: Systems Thinking + Subsystems

What you're submitting today

First systems diagram of the year. Formative: scored as practice, not summative. Maps to T/T Thinking.

Checkpoint: hand this in at the end

Your systems diagram, plus one sentence on what puts buried matter back into circulation. Feedback only, no band. It is practice for the thinking that Block 7 gets graded on.

Exit ticket (submit by end of class)

A photo or scan of your systems diagram. Must include all four subsystems labeled, at least three interaction arrows with verbs, one feedback loop labeled + or − with a one-sentence justification, and one sentence on what puts buried matter back into circulation. Worth doing: put your morning sketch next to the diagram in the photo; the distance between the two drawings is today's learning, visible.

Submit via Google Classroom (link posted in August)

Rubric link: Today is formative T/T practice: no scored band yet. The Goldilocks Report (Block 9) will score your final systems-thinking work against the T/T rubric.

One question before you leave

Three to five minutes. Your answer is saved to your reflection journal, where you can read back everything you have written this year.

Self-assessment against today's success criteria.

Today's reflection is in Google Classroom, under Reflection Journal.

Link posted in August

Sign in with your school account. Your teacher can see what you write here.