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Curriculum

Skill Tree

Complete lessons to earn XP, unlock achievements, and advance through every earth science discipline.

Foundations
Earth Foundations
How our planet is built — from deep interior to the minerals, rocks, and tectonic forces that shape its surface.
Unlocks Deep Time
Earth Foundations Graduate+750 XP
1
Earth's Interior
0/6000/4
1
Earth's Internal Structure
FREE
2
The Crust — Continental vs. Oceanic
FREE
3
The Mantle and Its Convection
FREE
4
Earth's Core and Magnetic Field
FREE
2
Minerals & Crystals
0/6000/4
1
What Defines a Mineral
FREE
2
Identifying Minerals — Hardness, Streak, and Cleavage
FREE
3
The Rock-Forming Minerals
FREE
4
Crystal Systems — Introduction
FREE
3
The Rock Families
0/6000/4
The Rock Cycle Overview
150
Igneous Rocks
150
Sedimentary Rocks
150
Metamorphic Rocks
150
4
Plate Tectonics
0/6000/4
The Theory of Plate Tectonics
150
Plate Boundaries
150
Subduction and Orogenesis
150
Hotspots and Mantle Plumes
150
5
Surface Processes
0/6000/4
Volcanic Landforms
150
Weathering and Erosion Landforms
150
River Systems and Landscapes
150
Glacial and Coastal Landforms
150
6
Path Assessment
0/5000/1
Earth Foundations Final Exam
500
Intermediate
Deep Time
Naturalist plan required — upgrade to unlock
Deep Time Graduate+1,500 XP
1
Geologic Time
0/1,0000/4
Deep Time: From Hutton to Today
250
Relative Dating Principles
250
Radiometric Dating Methods
250
Calibrating the Geologic Timescale
250
2
Rock Records & Stratigraphy
0/1,0000/4
Sedimentary Sequences and Facies
250
Unconformities and Missing Time
250
Sequence Stratigraphy Basics
250
Reading a Stratigraphic Column
250
3
The Fossil Record
0/1,0000/4
How Fossils Form
250
Biostratigraphy and the Fossil Clock
250
Trace Fossils and Ichnology
250
Lagerstätten: Windows into Ancient Life
250
4
Life Through the Ages
0/1,0000/4
The Cambrian Explosion and Animal Origins
250
Mass Extinctions: Causes and Consequences
250
The Conquest of Land
250
The Cenozoic: Ice Ages, Mammals, and Modern Earth
250
5
Field Methods
0/1,0000/4
Reading Geological Maps and Cross-Sections
250
Structural Geology: Folds and Faults
250
Measuring and Recording Stratigraphic Sections
250
Rock and Mineral Identification in the Field
250
6
Path Assessment
0/5000/1
Deep Time Final Exam
500
Foundations
Ocean Systems
The ocean floor, seawater chemistry, global circulation, waves, and the ecosystems that depend on it all.
Unlocks Marine Chemistry & Biogeochemistry
Oceanographer+750 XP
1
The Ocean Basin
0/5800/4
1
Mapping the Ocean Floor
FREE
2
Mid-Ocean Ridges and Hydrothermal Vents
FREE
3
Trenches and the Deep Ocean
FREE
4
Seafloor Sediments and the Ocean Record
FREE
2
Seawater & Ocean Structure
0/5850/4
Salinity and Seawater Chemistry
140
Temperature, Density, and Ocean Structure
150
Ocean Circulation: Wind Gyres and Deep Currents
150
Waves, Tides, and Coastal Dynamics
145
3
Marine Life
0/5700/4
Marine Ecosystems and Food Webs
140
Phytoplankton and Primary Production
150
Coral Reefs and Tropical Marine Ecosystems
140
Polar Oceans and Ice-Edge Ecosystems
140
4
The Deep Ocean
0/5400/4
Hydrothermal Vents and Chemosynthetic Life
140
Ocean Acidification: Chemistry, Impacts, and Trajectories
140
Bioluminescence and the Dark Ocean: Life Adapted to Extreme Depths
130
Deep-Ocean Sediments, Mineral Resources, and the Future of the Seafloor
130
5
Path Assessment
0/5000/1
Ocean Systems — Final Exam
500
Foundations
Atmosphere & Weather
The invisible ocean above us — atmospheric layers, the energy budget, weather systems, and forecasting.
Unlocks Climate Dynamics & Variability
Meteorologist+750 XP
1
Atmospheric Structure
0/5600/4
1
Layers of the Atmosphere
FREE
2
Atmospheric Composition and Trace Gases
FREE
3
Solar Radiation and the Energy Budget
FREE
4
The Greenhouse Effect and Radiative Forcing
FREE
2
Weather Systems
0/5600/4
Air Masses, Fronts, and Mid-Latitude Weather
140
The Mid-Latitude Cyclone
140
Thunderstorms and Severe Weather
140
Tropical Cyclones: Hurricanes and Typhoons
140
3
Clouds & Forecasting
0/5600/4
Cloud Formation and Classification
140
Precipitation: Types, Processes, and Patterns
140
Atmospheric Stability and Convection
140
Numerical Weather Prediction and Forecasting
140
4
Extreme Weather Events
0/6000/4
Tropical Cyclones: Formation and Structure
150
Tornadoes and Severe Convection
150
Heat Waves, Drought, and Atmospheric Blocking
150
Blizzards, Ice Storms, and Winter Hazards
150
5
Path Assessment
0/5000/1
Atmosphere & Weather — Final Exam
500
Foundations
Volcanoes
Where the interior meets the surface — magma generation, eruption styles, and the hazards that follow.
Unlocks Magma Systems & Igneous Petrology
Volcanologist+750 XP
1
Magma & Volcanism
0/5600/4
1
The Origin of Magma
FREE
2
Magma Composition and Viscosity
FREE
3
Intrusive Igneous Bodies and Plutonism
FREE
4
Volcanic Landforms and Edifice Types
FREE
2
Eruption Styles
0/5600/4
Eruption Classification: VEI and Eruption Styles
140
Effusive Eruptions and Lava Flow Dynamics
140
Explosive Eruptions and Pyroclastic Density Currents
140
Volcanic Gases, Degassing, and the Atmosphere
140
3
Volcanic Hazards
0/5600/4
Lahars, Debris Avalanches, and Hydrological Hazards
140
Volcanic Tsunamis, Lateral Blasts, and Ballistic Hazards
140
Volcanic Winter, Ashfall, and Long-Range Atmospheric Hazards
140
Volcanic Monitoring, Risk Assessment, and Early Warning
140
4
Volcanic Legacy
0/6000/4
Volcanoes and Climate: Stratospheric Aerosols and Cooling
150
Supervolcanoes and Calderas
150
Volcanic Soils, Geothermal Energy, and Mineral Resources
150
Monitoring Volcanoes and Forecasting Eruptions
150
5
Path Assessment
0/5000/1
Volcanoes — Final Exam
500
Foundations
Climate, Past & Future
The climate system, its history over millions of years, and what rising CO₂ means for the planet ahead.
Unlocks Carbon Cycle & Climate Feedbacks
Climate Scientist+1,500 XP
1
The Climate System
0/5600/4
1
The Climate System: Components and Interactions
FREE
2
Atmospheric Circulation and the Ocean Heat Engine
FREE
3
The Carbon Cycle: Fast, Slow, and Human Perturbation
FREE
4
Climate Extremes: Heat Waves, Floods, and Attribution Science
FREE
2
Climate Through History
0/5600/4
Ice Ages and the Milankovitch Cycles
140
Abrupt Climate Change: Dansgaard-Oeschger Events and Tipping Points
140
The Holocene Climate and the Little Ice Age
140
Deep Time Climate: From Snowball Earth to the Greenhouse Cretaceous
140
3
Modern Climate Change
0/6000/4
Observed Warming: Instrumental Records and Attribution
140
Sea Level Rise, Ice Sheet Dynamics, and Cryosphere Change
140
Climate Impacts: Ecosystems, Food, Water, and Human Health
180
Mitigation, Adaptation, and Climate Policy
140
4
Responding to Climate Change
0/6000/4
The Energy Transition: Decarbonizing Power and Heat
150
Carbon Dioxide Removal: Sinks, Machines, and Oceans
150
Adaptation: Living with a Changing Climate
150
Solar Geoengineering: Risks and Governance
150
5
Path Assessment
0/5000/1
Climate, Past & Future — Final Exam
500
Foundations
Solar System
From dust to worlds — how our solar system formed, and what comparative planetology reveals about each body.
Unlocks Planetary Geology
Solar System Explorer+750 XP
1
Solar System Formation
0/5600/4
1
The Nebular Hypothesis and Formation of the Solar System
FREE
2
Differentiation, Accretion, and the Late Heavy Bombardment
FREE
3
The Sun: Structure, Energy Generation, and the Solar Wind
FREE
4
Comparative Planetology: Rocky Worlds vs. Giant Planets
FREE
2
Terrestrial Worlds
0/5600/4
Mercury and Venus: Extremes of the Inner Solar System
140
Mars: The Red Planet and Its Geological History
140
Earth's Moon: A Geological Record in Plain Sight
140
Asteroids, Meteorites, and the Asteroid Belt
140
3
Gas Giants
0/5600/4
Jupiter: Internal Structure, Atmosphere, and Magnetosphere
140
Jupiter's Galilean Moons: Io, Europa, Ganymede, and Callisto
140
Saturn: Rings, Atmosphere, and the Ringed World
140
Saturn's Moons: Titan and Enceladus — Astrobiology's Frontier
140
4
Ice Giants & Beyond
0/5600/4
Uranus: The Tilted Ice Giant
140
Neptune: Supersonic Winds and a Captured Moon
140
The Kuiper Belt and Pluto: Worlds Beyond Neptune
140
Comets, the Oort Cloud, and Interstellar Visitors
140
5
Path Assessment
0/5000/1
Solar System — Path Assessment
500
Foundations
Earthquakes & Seismology
From P-waves to fault rupture — seismic waves, earthquake mechanics, ground motion hazards, and the science of keeping communities safe.
Unlocks Advanced Seismology
Seismologist+750 XP
1
Seismic Waves
0/4800/4
1
P-Waves, S-Waves, and the Seismic Wave Family
FREE
2
How Seismic Waves Travel Through the Earth
FREE
3
Seismographs, Seismograms, and Locating Earthquakes
FREE
4
Earth's Interior Revealed by Seismology
FREE
2
Earthquake Mechanics
0/4800/4
Faults, Rupture, and the Elastic Rebound Theory
120
Measuring Earthquake Size: Magnitude and Intensity
120
Focal Mechanisms and Stress in the Crust
120
The Seismic Cycle and Earthquake Recurrence
120
3
Earthquake Hazards & Resilience
0/5200/4
Ground Motion, Amplification, and Building Response
130
Liquefaction, Landslides, and Secondary Hazards
130
Seismic Tsunamis: Generation, Propagation, and Runup
130
Earthquake Early Warning, Forecasting, and Resilience
130
4
Seismic Risk and Society
0/6000/4
Probabilistic Seismic Hazard Analysis
150
Earthquake Early Warning Systems
150
Seismic Engineering and Building Codes
150
Induced Seismicity: When Humans Trigger Earthquakes
150
5
Path Assessment
0/5000/1
Earthquakes & Seismology: Path Assessment
500
Foundations
Hydrology
The water cycle, rivers and floods, and groundwater — how freshwater moves through, shapes, and sustains our world.
Unlocks Advanced Hydrology
Hydrologist+750 XP
1
The Water Cycle
0/4800/4
1
The Global Water Cycle and Water Budget
FREE
2
Precipitation, Evapotranspiration, and the Energy Balance
FREE
3
Infiltration, Soil Moisture, and Runoff Generation
FREE
4
Snow Hydrology and the Mountain Water Tower
FREE
2
Rivers & Watersheds
0/4800/4
Drainage Basins, Stream Networks, and Watershed Geometry
120
Stream Discharge, Rating Curves, and Flood Hydrographs
120
Fluvial Geomorphology: How Rivers Shape Landscapes
120
Flood Hazards, Floodplains, and Flood Risk Management
120
3
Groundwater
0/5200/4
Aquifers, Porosity, and Groundwater Hydraulic Properties
130
Groundwater Flow, Darcy's Law, and Well Hydraulics
130
Springs, Geothermal Systems, and Groundwater-Surface Water Exchange
130
Groundwater Depletion, Contamination, and Sustainability
130
4
Water Resources and Society
0/6000/4
Global Freshwater Scarcity and the Water Cycle's Future
150
Dams, Reservoirs, and River Management
150
Agriculture, Irrigation, and the Water–Food–Energy Nexus
150
Floods: Frequency, Risk, and the Future
150
5
Path Assessment
0/5000/1
Hydrology: Path Assessment
500
Foundations
Geomorphology
How landscapes form and evolve — weathering, rivers, coasts, dunes, karst, and permafrost shaping Earth's surface over millions of years.
Geomorphologist+750 XP
1
Weathering, Soils, and Hillslopes
0/4800/4
1
Chemical and Physical Weathering
FREE
2
Regolith, Saprolite, and Soil Formation
FREE
3
Mass Wasting: Landslides, Debris Flows, and Slope Failure
FREE
4
Hillslope Processes and Landscape Evolution
FREE
2
Rivers, Coasts, and Deltas
0/4800/4
River Channel Morphology and Sediment Transport
120
Floodplains, River Terraces, and Tectonic Geomorphology
120
Deltas, Estuaries, and Coastal Landforms
120
Wave Processes and Rocky Coastline Evolution
120
3
Aeolian, Karst, and Periglacial
0/5200/4
Wind Erosion, Deflation, and Desert Landforms
130
Dune Types, Loess, and Desertification
130
Karst Landscapes, Caves, and Speleothems
130
Periglacial Processes and Permafrost
130
4
Tectonic Geomorphology and Hazards
0/6000/4
Tectonic Geomorphology: Landscapes Shaped by Faults and Uplift
150
Landslides and Mass Wasting Hazards
150
Coastal Geomorphology and Sea Level Change
150
Human Geomorphology: How We Reshape the Land
150
5
Path Assessment
0/5000/1
Geomorphology: Path Assessment
500
Foundations
Glaciology
From snowflake to ice sheet — the physics of glaciers, the dynamics of polar ice, and what frozen archives reveal about Earth's climate history.
Glaciologist+750 XP
1
Snow, Ice, and Glacier Dynamics
0/4800/4
1
Snow Metamorphism and Ice Formation
FREE
2
Glacier Flow and Ice Dynamics
FREE
3
Glacier Mass Balance and Climate Response
FREE
4
Types and Global Distribution of Glaciers
FREE
2
Ice Sheets and Sea Ice
0/4800/4
The Greenland Ice Sheet: Structure, Dynamics, and Change
120
The Antarctic Ice Sheet: Continent of Ice
120
Sea Ice: Physics, Ecology, and Arctic Change
120
Ice Shelves, Grounding Lines, and Marine Ice Sheet Instability
120
3
Glacial Landforms and Climate Archives
0/5200/4
Glacial Erosion and the Landscapes Ice Carves
130
Glacial Sediments, Till, and Depositional Landforms
130
Sea Level Change, Ice Volume, and Glacial Isostasy
130
Ice Cores and Paleoclimate: Reading Frozen Archives
130
4
Ice in a Warming World
0/6000/4
Measuring Glacier Retreat: Mass Balance and Remote Sensing
150
Ice Sheets, Marine Ice Instability, and Sea Level Futures
150
Permafrost Thaw and Arctic Feedbacks
150
Glacial Hazards: Floods, Avalanches, and Ice Collapse
150
5
Path Assessment
0/5000/1
Glaciology: Path Assessment
500
Intermediate
Marine Chemistry & Biogeochemistry
Naturalist plan required — upgrade to unlock
1
Ocean Chemistry & Dissolved Gases
0/5200/4
Seawater Carbonate Chemistry
130
Ocean Acidification
130
Dissolved Oxygen and Ocean Dead Zones
130
Marine Nutrient Cycles
130
2
Marine Carbon Export & Storage
0/5200/4
The Biological Pump
130
Marine Primary Production
130
Deep-Sea Carbon Storage
130
Methane Hydrates
130
3
Ocean–Climate Coupling
0/5200/4
ENSO — El Niño, La Niña, and the Walker Circulation
130
Ocean Heat Content and the Energy Budget
130
AMOC and the Thermohaline Circulation
130
Sea Ice and Polar Oceanography
130
4
The Anthropocene Ocean
0/8000/4
Marine Heat Waves
200
Ocean Deoxygenation
200
Ocean-Based Carbon Dioxide Removal
200
Future Ocean Projections
200
5
Path Assessment
0/5000/1
Marine Chemistry & Biogeochemistry: Capstone Assessment
500
Intermediate
Carbon Cycle & Climate Feedbacks
Naturalist plan required — upgrade to unlock
1
The Global Carbon Cycle
0/5200/4
The Global Carbon Cycle
130
Land Carbon Sinks and Sources
130
Ocean Carbon Uptake
130
The Carbon Budget and Remaining Emissions
130
2
Climate Sensitivity & Feedbacks
0/5200/4
Climate Sensitivity and Radiative Forcing
130
Water Vapour and Lapse Rate Feedbacks
130
Cloud and Albedo Feedbacks
130
Carbon Cycle Feedbacks & Climate Sensitivity
130
3
Tipping Points, Models & Futures
0/5200/4
Climate Tipping Points & Cascades
130
Earth System Models & Climate Simulation
130
Climate Projections & Emissions Scenarios
130
Carbon Removal & Climate Intervention
130
4
Paleoclimate Proxies and Model-Data Comparison
0/8000/4
Ice Core Archives
200
Ocean Sediments and Speleothems
200
Tree Rings, Pollen, and High-Resolution Proxies
200
Multi-Proxy Synthesis and Model-Data Comparison
200
5
Path Assessment
0/5000/1
Carbon Cycle & Climate Feedbacks: Capstone Assessment
500
Intermediate
Magma Systems & Igneous Petrology
Naturalist plan required — upgrade to unlock
1
Magma Genesis & Differentiation
0/5200/4
Partial Melting & Magma Genesis
130
Bowen's Reaction Series & Magmatic Differentiation
130
Magma Types & Tectonic Settings
130
Large Igneous Provinces & Mantle Plumes
130
2
Magmatic Systems & Calderas
0/5200/4
Magma Chambers & Crystal Mush Systems
130
Calderas & Supervolcanoes
130
Oceanic Island Volcanism & Hotspot Chains
130
Subduction Zone Geochemistry & Arc Magmas
130
3
Planetary Volcanology & Tracers
0/5200/4
Planetary Volcanism Across the Solar System
130
Flood Basalts & Mass Extinctions
130
Mid-Ocean Ridge Volcanism & MORB
130
Volcanic Geochemistry & Isotopic Tracers
130
4
Eruption Dynamics and Applied Volcanology
0/8000/4
Eruption Column Physics
200
Lava Flow Modeling
200
Volcanic Gas Monitoring
200
Volcanic Hazard Mapping and Crisis Communication
200
5
Path Assessment
0/5000/1
Magma Systems & Igneous Petrology: Capstone Assessment
500
Intermediate
Climate Dynamics & Variability
Naturalist plan required — upgrade to unlock
1
Climate Modes & Teleconnections
0/5200/4
ENSO & Atmospheric Teleconnections
130
Pacific Decadal Oscillation & Atlantic Multidecadal Oscillation
130
North Atlantic Oscillation & Arctic Oscillation
130
Asian Monsoon & Tropical Circulations
130
2
Dynamic Meteorology
0/5200/4
Jet Streams & Rossby Waves
130
Atmospheric Blocking & Persistent Weather Patterns
130
Cyclogenesis & Explosive Deepening
130
Mesoscale Convective Systems & Severe Weather
130
3
Atmospheric Extremes
0/5200/4
Heat Waves, Drought & Compound Extremes
130
Atmospheric Rivers & Extreme Precipitation
130
Tropical Cyclone Intensification & Climate
130
Polar Vortex & Sudden Stratospheric Warming
130
4
Numerical Weather Prediction and Predictability
0/8000/4
Data Assimilation and Observation Networks
200
Ensemble Forecasting and Uncertainty
200
Predictability Limits and Chaos Theory
200
Machine Learning in Weather Forecasting
200
5
Path Assessment
0/5000/1
Climate Dynamics & Variability: Capstone Assessment
500
Foundations
Astrobiology
From the origin of life on Earth to the search for it elsewhere — prebiotic chemistry, habitable worlds, and the cosmos as a life-detection problem.
Astrobiologist+750 XP
1
Origins of Life
0/4800/4
1
Chemical Evolution and the Origin of Life
FREE
2
Early Earth and the First Life
FREE
3
Extremophiles and the Limits of Life
FREE
4
Photosynthesis and the Great Oxidation Event
FREE
2
Habitable Worlds in the Solar System
0/4800/4
Mars Habitability Past and Present
120
Europa and Icy Ocean Worlds
120
Titan: An Organic World
120
Venus and the Runaway Greenhouse
120
3
Exoplanets and the Search for Life
0/5200/4
Detecting Exoplanets
130
Habitable Zones and Planetary Conditions
130
Biosignatures and the Search for Life
130
The Fermi Paradox and the Drake Equation
130
4
The Search for Life Beyond Earth
0/6000/4
Mars: From Ancient Habitability to Modern Search
150
Ocean Worlds: Europa, Enceladus, and Titan
150
Reading the Light: Atmospheric Biosignatures and JWST
150
The Fermi Paradox and the Search for Technological Life
150
5
Path Assessment
0/5000/1
Astrobiology: Path Assessment
500
Intermediate
Planetary Geology
Naturalist plan required — upgrade to unlock
Planetary Geologist+1,500 XP
1
Impact Cratering and Planetary Surfaces
0/8000/4
Impact Cratering Mechanics
200
Crater Morphology and Classification
200
The Lunar Cratering Record and Planetary Chronology
200
Impact Hazards on Earth
200
2
Planetary Atmospheres and Climate
0/8000/4
Atmospheric Origin and Evolution
200
The Runaway Greenhouse: Venus and the Limits of Habitability
200
Mars: From Thick Atmosphere to Thin
200
Titan's Atmosphere and Organic Chemistry
200
3
Planetary Interiors and Tectonics
0/8000/4
Methods for Probing Planetary Interiors
200
Planetary Magnetic Fields and Dynamos
200
Stagnant Lid Tectonics and Why Earth is Unique
200
Volcanism Across the Solar System
200
4
Path Assessment
0/5000/1
Planetary Geology: Capstone Assessment
500
Intermediate
Advanced Seismology
Naturalist plan required — upgrade to unlock
Advanced Seismologist+1,500 XP
1
Seismic Tomography and Earth Structure
0/8000/4
Body Wave Tomography
200
Surface Wave Tomography and Ambient Noise
200
Seismic Discontinuities and the Transition Zone
200
Mantle Plumes and Subducting Slabs in Tomographic Images
200
2
Earthquake Source Physics
0/8000/4
Seismic Moment and Rupture Dynamics
200
Fault Friction and Rate-State Laws
200
Paleoseismology and the Long-Term Earthquake Record
200
Slow Earthquakes and the Tremor-Slip Spectrum
200
3
Geodesy and Crustal Deformation
0/8000/4
GPS and Geodetic Measurement of Plate Motion
200
InSAR and the Surface Deformation Record
200
Subduction Zone Coupling and Tsunami Potential
200
Volcano-Seismic Systems and Eruption Forecasting
200
4
Path Assessment
0/5000/1
Advanced Seismology: Capstone Assessment
500
Intermediate
Advanced Hydrology
Naturalist plan required — upgrade to unlock
Advanced Hydrologist+1,500 XP
1
Catchment Hydrology and Process Hydrology
0/8000/4
Runoff Generation Mechanisms
200
Hydrograph Analysis and Unit Hydrograph Theory
200
Streamflow Routing and Open Channel Hydraulics
200
Catchment Water Balance and the Budyko Framework
200
2
Ecohydrology and Water Quality
0/8000/4
Transpiration, Stomatal Conductance, and Ecohydrology
200
Nutrient Cycling and Water Quality in Watersheds
200
Sediment Transport and River Geomorphodynamics
200
Contaminant Hydrogeology
200
3
Global Hydrology and Water Resources
0/8000/4
Streamflow Trends Under Climate Change
200
Hydrological Extremes: Floods and Droughts
200
Cryosphere-Hydrology Interactions
200
Integrated Water Resource Management
200
4
Path Assessment
0/5000/1
Advanced Hydrology: Capstone Assessment
500