From tiny things
to very big ideas.

Follow a blood cell; vary a reviewed activity preset and inspect valves.

Body → circulation → chambers → valves

Move the diaphragm; trace air and gas exchange in an alveolus.

Chest → lungs → alveolus → membrane

Follow a meal and inspect how different nutrients are broken down and absorbed.

Digestive tract → intestine → villus → molecule

Trace filtration and reabsorption through a nephron using reviewed presets.

Body → kidney → nephron → membrane

Trace a nutrient through processing, storage, and release.

Organ → lobule → cell → chemical pathway

Contract a muscle pair; inspect tendons, leverage, and muscle fibers.

Limb → joint → muscle → sarcomere

Follow an immune response and compare innate and adaptive stages.

Body → tissue → immune cell → receptor

Compare a first encounter with a later response in an explicitly simplified model.

Immune system → cell interactions → memory

Change a reviewed meal/activity preset and trace feedback signals.

Body → pancreas and liver → cells → receptors

Scrub developmental stages and inspect placenta, cell division, and specialization.

Reproductive system → embryo → tissue → cell

Trigger a signal and trace a membrane impulse and synapse.

Neural pathway → neuron → synapse → ion channel

Move an object; follow focusing and retinal signals.

Eye → lens → retina → photoreceptor

Change frequency and inspect the eardrum, ossicles, and cochlea.

Ear → middle ear → cochlea → hair cell

Tilt a head model and inspect vestibular signals.

Head → inner ear → canals and otoliths

Compare stimuli and trace distinct sensory pathways.

Skin → receptor → nerve → spinal cord

Trace a reflex arc and compare its timing with conscious processing.

Body → spinal cord → neuron circuit

Explore a clearly labeled network analogy alongside what experiments establish.

Brain systems → circuit → synapse

Move light exposure on a day/night timeline and inspect the two-process model.

Daily rhythm → brain systems → signaling

Compare odor and taste signals and see how they contribute to flavor.

Mouth and nose → receptors → neural pathways

Try controlled visual illusions and compare interpretation with the stimulus.

Stimulus → percept → explanatory model

Inspect organelles and follow energy and material through selected pathways.

Organism → tissue → cell → organelle

Change a supported concentration and compare diffusion, osmosis, and transport.

Cell → membrane → channel → molecule

Follow transcription and translation and change a model sequence.

Chromosome → gene → RNA → protein

Scrub mitosis and inspect chromosome copying and separation.

Cell → chromosome → spindle

Explore simple inheritance first, then expose its limits for complex traits.

Family → chromosome → allele

Vary heritable traits and environment in a bounded population model.

Ecosystem → population → individual → gene

Compare microbial structures and selected ecological roles.

Environment → community → microbe → cell

Trace a representative viral life cycle and distinguish it from a cell.

Host → cell → virus → genome

Trace light, water, and carbon through a simplified chloroplast model.

Plant → leaf → chloroplast → reaction

Trace glucose and oxygen through an explicitly simplified energy pathway.

Cell → mitochondrion → membrane → molecules

Turn an input gear; swap gear pairs and compare rotation and ideal torque.

Machine → gear train → tooth contact

Move a fulcrum or reroute a pulley; compare force and travel.

Machine → force diagram → contact

Compare sliding and rolling interfaces under documented assumptions.

Assembly → bearing → contact patch

Change crank or cam geometry and trace the output path.

Mechanism → linkage → follower

Scrub intake, compression, power, and exhaust in a cutaway.

Engine → cylinder → valve train → cycle

Press a pedal; inspect hydraulic pressure, caliper motion, and friction.

Vehicle → brake circuit → caliper → contact

Change current polarity and inspect coils, magnets, and torque.

Motor → rotor and stator → magnetic field

Select ratios and turn through a corner to inspect wheel speeds.

Drivetrain → gearbox → differential

Trace air through a representative compressor, combustor, and turbine.

Engine → stages → blade row → flow

Move a target; explore joint limits, reach, and alternative poses.

Robot → joints → actuator → feedback

Connect simple components and compare current, voltage, and resistance.

Circuit → component → schematic

Rewire series and parallel branches and open one connection.

Network → branch → component

Charge and discharge through a resistor; inspect fields and a voltage graph.

Circuit → capacitor → plates → field

Trace ions and electrons through one documented rechargeable chemistry.

Device → cell → electrodes → ions

Spin a coil and compare the induced voltage as orientation changes.

Generator → coil → magnetic field

Change ideal winding counts, then reveal real losses and limits.

Grid → transformer → windings → core

Vary light and inspect a simplified semiconductor junction.

Panel → cell → junction → charge carrier

Change wind and blade pitch within a documented operating envelope.

Turbine → rotor → drivetrain → generator

Balance a small illustrative grid and trace generation to distribution.

Region → substation → feeder → home

Follow a bounded, non-operational chain-reaction model into a heat cycle.

Plant → reactor → fuel → nucleus

Toggle bits, compose gates, and inspect a small adder.

Device → circuit → gate → bit

Vary a simplified input and connect switching behavior to a logic gate.

Chip → transistor → channel → charge

Step through fetch, decode, execute, and a small memory transaction.

Computer → CPU → datapath → register

Send a model message; introduce delay or loss and trace routing and reassembly.

Devices → network → router → packet

Follow DNS, connection setup, request, and response in a protocol timeline.

Browser → DNS → server → resource

Change a model signal and noise; inspect encoding, transmission, and reception.

Network → link → signal → symbol

Compare lossless coding with lossy quantization using small examples.

Media → samples → encoded representation

Explore a toy key exchange and authenticated encryption concepts, clearly separated from production security.

Message → protocol → mathematical operation

Train a small classifier; change examples and inspect errors on held-out data.

Dataset → model → decision boundary

Inspect tokens and a small illustrative attention model; vary context and sampling.

Text → tokens → attention → probability

Brake one car, change density or spacing, and compare a matched no-braking road.

Road → queue → following pair → model

Adjust signal offsets and demand in a small corridor model.

Corridor → junction → signal phase

Compare a controlled junction and a roundabout under stated demand assumptions.

Street network → intersection → vehicle conflict

Separate reaction distance from braking distance; vary supported speed and grip.

Road → vehicle → tire-road contact

Change frequency and transfers; compare waiting and travel time.

City → route → stop → journey

Place loads and inspect a simple truss, beam, and suspension model.

Bridge → member → force path

Change stiffness or damping and apply a bounded base-motion input.

Building → floor → frame → damper

Trace treatment, storage, pumping, and pressure through a town.

Watershed → treatment plant → pipe → tap

Follow screening, biological treatment, and separation in a representative plant.

Neighborhood → plant → tank → microbes

Change angle of attack and inspect pressure and momentum explanations within a validated model.

Aircraft → wing → airflow → force

Build a symbolic atom and connect proton count, isotopes, and ions.

Material → atom → nucleus and electrons

Compare representative bonding models and their limits.

Material → molecule or lattice → bond

Change temperature and pressure in a documented phase model.

Bulk matter → particles → interaction

Rearrange model atoms and balance a simple reaction.

Reactants → bond changes → products

Compare bounded acid/base examples and follow a neutralization model.

Solution → ions → proton transfer

Change solvent, temperature, or concentration in a selected system.

Mixture → interface → molecule

Compare supported reaction pathways and an activation-energy diagram.

Reaction system → pathway → active site

Compare chain structures and documented thermal and mechanical behavior.

Object → polymer network → chain

Trace a representative electrochemical corrosion process.

Object → surface → electrochemical site

Inspect crystals, defects, and composite layers under simplified loading.

Component → microstructure → lattice

Change a bounded weather input and follow evaporation, condensation, and runoff.

Planet → watershed → cloud → droplet

Compare air parcels and read a simplified weather map.

Region → air mass → parcel

Change parcel conditions and inspect condensation and droplet growth.

Atmosphere → cloud → droplet

Inspect separate storm mechanisms using reviewed presets.

Weather system → circulation → updraft

Move plate boundaries and inspect selected crustal processes.

Planet → plate → boundary → rock

Load a bounded fault model and trace seismic waves.

Region → fault → rupture → waves

Inspect representative volcano types and a bounded eruption model.

Plate setting → volcano → conduit → magma

Vary a simplified atmosphere and track incoming and outgoing energy.

Planet → atmosphere → radiation bands

Compare a documented energy-balance model with and without selected feedbacks.

Global system → feedback loop → process

Inspect wind-driven and density-driven circulation separately.

Ocean basin → current → water parcel

Change one population in a bounded food-web model.

Ecosystem → food web → population

Vary resources and reproduction in documented growth models.

Habitat → population → individual

Follow pollen between flowers and compare reproductive structures.

Landscape → flower → pollen → seed

Inspect water, minerals, roots, and decomposers through a soil profile.

Field → soil layer → pore → organism

Trace xylem and compare transpiration under reviewed conditions.

Plant → root and leaf → xylem → stoma

Follow reservoirs and fluxes in a bounded carbon-cycle model.

Planet → reservoir → organism → molecule

Trace fixation, uptake, and return through organisms and soil.

Ecosystem → soil → microbe → molecule

Compare explicitly limited ecosystem scenarios and discuss model uncertainty.

Landscape → community → species → genes

Use a documented crop example to compare irrigation and resource constraints.

Farm → field → plant → roots

Compare representative fermentation pathways and track inputs and products.

Food → microbial population → cell → pathway

Change a model launch velocity and inspect trajectories.

Planetary system → orbit → force

Tilt Earth and move it around the Sun; compare sunlight across latitudes.

Solar system → Earth → latitude

Move Sun, Earth, and Moon and compare lit geometry with the observer's view.

System → alignment → shadow → observer

Inspect differential gravity and distinguish an idealized tide model from local coastlines.

Earth-Moon system → ocean → coastline

Scrub representative stellar tracks and inspect pressure and energy generation.

Star → layers → core → fusion

Explore a labeled formation model and the observations supporting it.

Disk → planetesimal → planet

Vary a bounded mass-flow model and compare momentum and fuel use.

Mission → rocket → engine → exhaust

Compare orbits and light paths in explicitly scoped spacetime models.

Galaxy → black hole → horizon → light path

Change an orbit and observe transit and radial-velocity signals.

Star system → orbit → observation → signal

Change the scale of a model space and compare distances and redshift.

Cosmic structure → galaxies → observation

Apply forces and compare motion with a synchronized force diagram.

Scene → object → vectors

Vary mass and velocity in bounded collision models.

System → collision → energy and momentum plots

Send a pulse through a medium and track individual elements.

Medium → wave → element → oscillation

Sweep a driving frequency and compare resonance and damping.

Instrument → resonator → vibration

Move an object and change a lens; connect ray diagrams with image formation.

Optical system → lens → rays → image

Compare spectra, filters, additive light mixing, and material absorption.

Scene → spectrum → interaction

Change wavelength or slit spacing in a documented wave model.

Wavefront → aperture → interference pattern

Compare conduction, convection, and radiation in separate bounded cases.

Object → interface → material → particles

Change density and displacement and inspect pressure with depth.

Fluid → object → force diagram

Move along frequency scales and compare interaction with selected materials.

Wave → spectrum → detector

Scale an object and compare length, area, and volume.

Object → dimensions → equation

Compare linear and exponential change on shared time scales.

Repeated process → graph → equation

Run repeatable seeded coin and dice experiments and compare counts.

Single trial → sample → distribution

Filter a transparent population and compare base rates and conditional counts.

Population → subset → probability

Sample from a known population and compare estimates and uncertainty.

Population → sample → statistic

Add or remove edges and compare paths and connected components.

Network → community → node → edge

Change arrival and service rates in a documented queue model.

Service system → queue → customer

Change a target or disturbance and compare control responses.

System → feedback loop → controller → sensor

Compare search strategies on a small visible problem.

Problem → candidate space → algorithm

Play transparent payoff games and compare strategies and collective outcomes.

Group → players → choices → payoffs

Trace a refrigerant cycle and inspect compressor, valves, and coils.

Appliance → cycle → component → fluid

Inspect a simplified field and heating model; distinguish absorbed energy from temperature.

Appliance → cavity → field → material

Inspect coil fields and induced currents in suitable cookware.

Appliance → coil → pan → current

Trace a cycle and inspect mechanical action, drainage, and spin balance.

Appliance → drum → water and fabric

Change aperture, shutter time, and focus in a defined optical model.

Camera → lens and shutter → sensor → pixel

Inspect representative transducers and compare input and output signals.

Device → diaphragm → coil → field

Inspect a simplified capacitive grid and compare touch locations.

Device → sensor grid → electric field

Slice a small model and inspect toolpaths and layer deposition for one process.

Object → layer → toolpath → material

Compare selected filtration mechanisms and explicitly bounded removal claims.

System → medium → pore → particle

Inspect a representative traction system and trace motion, counterweight, and stopping.

Building → lift system → drive → control

Design a controlled virtual experiment and compare competing explanations.

Question → hypothesis → experiment → evidence

Change instrument resolution and repeat measurements of a known quantity.

Object → instrument → reading → uncertainty

Compare observational patterns with controlled interventions in transparent examples.

Dataset → relationship → causal model

Compare models of the same system and inspect domains where each fails.

Real system → abstraction → prediction → validation

Track an explicit energy budget through motion, heating, and losses.

System → transfer → energy ledger

Compare carefully scoped particle and heat-flow models; reveal the statistical description.

System → macrostate → microstates

Compare inertial frames with a light-clock and spacetime diagram.

Events → reference frame → spacetime geometry

Change a supported measurement setup and compare distributions, not invented literal particle paths.

Experiment → quantum state → probability → detection

Compare nearly identical starting conditions in a documented dynamical model.

System → trajectories → state space

Compare predictions, evidence, revision, and unresolved questions in historical cases.

Observation → model → evidence → theory