AC Circuits: Impedance and Phase Shift
Compare R, RC, RL, and RLC circuits, phase shift, impedance, and resonance.
LaunchAll Simulations
Choose simulations in physics, chemistry, biology, and math and start a lesson in minutes
Amino Acids and Proteins: how a protein molecule is built
Understand how amino acids join into proteins and why protein structure matters.
LaunchAmmonia Molecule (NH₃): shape, bonds, and polarity
Understand why ammonia has a trigonal pyramidal shape and why NH₃ is polar.
LaunchSelective Animal Breeding: Create a New Breed
Understand how parent selection and generation-by-generation selection produce a new animal breed.
LaunchApollo Parachute Descent
Configure Apollo’s parachute descent and see how deployment timing and Euler’s method affect a safe splashdown.
LaunchApollo: Re-entry
Test Apollo return trajectories, hit the safe corridor, and see why mathematics and computation mattered for bringing the capsule home.
LaunchAtom, Orbitals, and Quantum Numbers (s/p/d/f)
Build electron configurations and test orbital filling with quantum numbers.
LaunchBlood Circulation: Heart, Loops, and Oxygen
Trace pulmonary and systemic loops, oxygen saturation, and how activity changes heart rate and flow.
LaunchBreathing and Gas Exchange: How the Body Gets Oxygen
Follow air to the alveoli, track O₂/CO₂ exchange with blood, and compare rest vs load breathing.
LaunchBuild the Nucleus
Build isotopes, vary N/Z ratio, and test which nuclei remain stable.
LaunchBuoyancy: why does it float or sink?
Test buoyancy in liquids and predict when objects float, sink, or stay suspended.
LaunchCapacitor: Field, Energy, and RC Charging
Charge and discharge an RC circuit, then track capacitance, field, and time constant.
LaunchCharges and Fields
Place charges and explore field lines, vectors, and electric field strength.
LaunchChemical Bonding and Molecular Geometry: Lewis + VSEPR
Build Lewis structures, compare VSEPR shapes, and estimate molecular polarity.
LaunchChemical Equilibrium: Le Chatelier Principle
Change concentration, volume, and temperature and predict shifts using Q and K.
LaunchCircular Motion: Centripetal Force
Explore circular motion and test how speed and radius set centripetal force.
LaunchCollisions: Momentum and Energy
Compare elastic and inelastic collisions and verify momentum conservation.
LaunchCoordinates: Points, Symmetry, Transformations
Plot points, reflect shapes, and test transformations on the coordinate plane.
LaunchCovalent Bonding: how atoms share electrons
Understand how atoms share electrons and form covalent bonds.
LaunchCrack the Enigma
A simplified Bletchley Park learning simulation showing how crib-based reasoning and logical constraints reduce Enigma settings step by step.
LaunchDiffusion
Compare diffusion rates and track how concentration gradients vanish over time.
LaunchDigestion and Enzymes: How Food Turns Into Nutrients
Show the food pathway, carb/protein/fat breakdown, and small-intestine absorption with pH effects.
LaunchDiscover Neptune: how mathematics found an unseen planet
Investigate the perturbation of Uranus and tune Planet X to recreate the mathematical discovery of Neptune.
LaunchDiscover π: Newton, Generalized Binomial Series, and Slow Convergence
Advanced historical-mathematical simulation: estimate π from quarter-circle area using Newton’s generalized binomial expansion and integration, and see why this direct method converges painfully slowly.
LaunchEco-Balance: O₂-CO₂
Keep O2/CO2 and species counts in balance to maintain a stable ecosystem.
LaunchElectrolysis: what appears on electrodes?
Run electrolysis and predict cathode/anode products from ions and charge passed.
LaunchElectromagnetic Spectrum: One Wave - Different Frequencies
Compare EM bands from radio to gamma and connect wavelength with frequency and energy.
LaunchEnergy on Track
Launch the cart, track energy transfer, and estimate friction losses.
LaunchEvolution and Natural Selection
Study variation, natural selection, and inheritance through trait changes in a population.
LaunchForces and Motion
Adjust force, mass, and friction to see how motion changes on an inclined plane.
LaunchFractions: Parts, Number Line, Missions
Learn fractions as parts of a whole and equivalent forms (fraction, decimal, percent) with cards, number line, and missions.
LaunchGas Under Piston: P–V–T
Adjust gas volume and temperature under a piston, then test how P, V, and T are linked.
LaunchGeometric Optics
Trace rays in lenses and mirrors to determine image position and magnification.
LaunchIdeal Heat Engine: Efficiency and the Carnot Limit
Compare heat-engine efficiency and test the Carnot limit across reservoir temperatures.
LaunchHooke's Law: Spring and Energy
Test Hooke's law, spring energy, and energy exchange during oscillations.
LaunchHydrogen Bonding: why molecules attract
Understand how hydrogen bonding holds water molecules together and affects the properties of substances.
LaunchHydrostatic Pressure
Measure pressure at different depths and compare effects of fluid density and gravity.
LaunchWave Interference
Combine waves to observe interference patterns, diffraction, and node formation.
LaunchKepler's Laws
Test Kepler's laws by changing orbit shape, area sweep, and period-distance relation.
LaunchLever: torque and balance
Balance the lever, vary force and arm length, and see torque in action.
LaunchLimiting Reagent: Who Runs Out First?
Choose reactant amounts, find the limiting reagent, and predict product yield.
LaunchLines: y = kx + b
Build lines, find intercepts and intersections, and solve two-variable systems.
LaunchSystems of Linear Equations: Two Lines
Explore two lines, their intersection, and the three solution types of a linear system.
LaunchMagnetic Field and Induction: Magnet + Coil
Move a magnet through a coil and track flux, EMF, direction, and turns.
LaunchBuild a Base: Energy Balance
Plan power for N sols and remove day-night deficits in the Mars base grid.
LaunchBuilding a Bridge on Mars
Build a Mars bridge, test load limits, and compare stress, strain, and elasticity.
LaunchCell: Organelles and Transport
Explore organelles, membrane transport, and cell energy balance.
LaunchConnect the Circuit
Wire the base circuit, find connection errors, and achieve stable lamp power.
LaunchDNA: Structure, Replication, and Mutations
Explore base pairing, replication, and how mutations can change DNA sequences.
LaunchMartian Rabbits
Change habitat pressures and track which traits improve population survival.
LaunchPhotosynthesis: Limiting Factors
Explore how light, CO₂, water, and temperature constrain photosynthesis rate.
LaunchRobots on Mars
Build command routes, debug the algorithm, and guide the rover without errors.
LaunchLaunch the Rocket
Launch a Mars rocket and tune mass, fuel, and angle to reach the target orbit.
LaunchSend a Message to Earth
Send signals Earth-Mars and measure delay from distance and light-speed limits.
LaunchWater Mixing Dynamics
Mix two solutions and observe concentration leveling over time: C_final, t_mix, diffusion, and stirring.
LaunchMendel’s Laws: Trait Inheritance
Build Punnett squares and compare genotype and phenotype outcomes for monohybrid and dihybrid crosses.
LaunchMetallic Bonding: cations and the "electron gas"
Understand how metallic bonding leads to conductivity and malleability.
LaunchMitosis: How a Cell Divides
Walk through mitosis phases and track how chromosomes replicate, align, and separate into two daughter cells.
LaunchNervous System: Neuron, Impulse, and Synapse
Explore threshold firing, action potentials, refractory period, myelin-driven speed, and synaptic signal transfer.
LaunchInequalities on the Number Line
Explore strict and non-strict inequalities, intervals, systems, and unions on a number line.
LaunchDC Circuits Builder
Build DC circuits, measure voltage and current, and apply Ohm's law to solve tasks.
LaunchOrganic Chemistry: Isomerism and Functional Groups
Build isomers, identify functional groups, and compare key property trends.
LaunchElementary Particles
Classify quarks, leptons, and bosons and map them to fundamental interactions.
LaunchSimple Pendulum
Measure pendulum period and compare how length changes oscillation frequency.
LaunchPercentages and Discounts: Quick Understanding
Calculate discounts, markups, and tax, then verify answers with reverse tasks.
LaunchpH and Neutralization: Acid + Base
Mix acids and bases, track pH, and test neutralization with different concentrations.
LaunchPhase Transitions: Ice → Water → Steam
Heat and cool matter to track phase changes, latent heat, and temperature plateaus.
LaunchPhotoelectric Effect: Threshold Frequency and Stopping Voltage
Test threshold frequency, light intensity, and stopping voltage in the photoelectric effect.
LaunchPlant Breeding: Create a New Variety
Understand how repeated crossing and selection create new plant varieties.
LaunchWater Transport in Plants and Transpiration
Trace water from soil to leaves and test how humidity, temperature, wind, and light change transpiration.
LaunchProbability: frequency vs probability
Run repeated trials with a coin, die, and bag, then compare relative frequencies with theoretical probabilities.
LaunchProjectile Motion
Launch a projectile, vary angle and speed, and explore its flight path.
LaunchParabola: quadratic function y = ax² + bx + c
Explore how coefficients a, b, and c change the parabola, its vertex, axis of symmetry, and roots.
LaunchReaction Rate and Catalyst
Test how temperature, concentration, surface area, and catalyst change reaction rate.
LaunchRedox Reactions: who donates and who accepts electrons
Understand who donates electrons, who accepts them, and how redox reactions work.
LaunchRedox and Galvanic Cell: Build a Battery
Assemble a galvanic cell and track electron flow, ion transfer, and EMF.
LaunchSolutions and Dilutions: C₁V₁ = C₂V₂
Prepare and dilute solutions, apply C1V1 = C2V2, and verify concentrations.
LaunchStatistics: mean, median, mode, and outliers
Drag points on a number line and compare mean, median, mode, range, and the effect of outliers.
LaunchUnit Circle: sin and cos
Rotate the angle on the unit circle and see how cos(θ) and sin(θ) become the point coordinates.
Launch