Scientific inquiry
Test explanations and compare evidence.
Explore Scientific inquiryScience
Learn to test an explanation, inspect the evidence and revise a conclusion. Start with scientific inquiry; explore the authored high-school, AP preparation and college pathways below.
Choose a starting point
Biology
Investigate living systems, from cells to ecosystems.
Explore BiologyPhysics
Explore motion, forces and physical models.
Explore PhysicsScientific inquiry and measurement
12 lessons, six bounded CPU investigations, saved notebooks, a cumulative project and separate numerical and reasoning transfer checks. Scientific reasoning and physical technique still need human review.
Open scientific inquiryScience starter course · view its lessons and project
Design evidence that can change your mind
Separate an intervention from a misleading comparison, and precision from instrument bias.
Start with everyday situations, predict an outcome, and test your ideas. You need basic arithmetic, percentages and graph reading; explanations introduce additional ideas where needed. No coding or account is required. Every investigation has school, college and workplace extensions—you can choose any of them.
What you will learn
Design a controlled investigation, separate bias from noise, compare competing explanations, and qualify a conclusion using evidence.
Before you begin
- Compute an average and percentage.
- Read signed differences and substitute values in a simple formula.
- No programming or prior statistics is required for the guided experiments.
Open any topic directly. Review functions and graphs whenever useful.
Choose your scope
The original two-investigation starter remains available. Choosing the full course adds its published lessons to your selected scope; your earlier work stays saved. Skipping does not count as completion or understanding.
Free exploration: no completion scope selected yet. Project reports and independent evidence are tracked separately.
Course outline
Choose a unit, then open a lesson on its own page. This outline lists the sequence; it does not combine the full lessons into one page.
Make the comparison fair
Identify composition, instrument and order effects that can imitate a treatment effect, and distinguish noise from bias.
Does the treatment work, or did the groups differ?
○ Not marked complete · Included · Practice check available
Lesson preview
Can an apparent benefit reverse while the treatment itself stays unchanged?
Original synthetic study: a fictional practice activity adds the same number of score points to two groups with different starting scores.
Why more measurements can still be wrong
○ Not marked complete · Included · Practice check available
Lesson preview
Does repeating a measurement remove every kind of error?
Original synthetic instrument: measure a known 10 cm reference with a fixed offset and a repeating disturbance pattern.
How averaging changes noisy evidence
○ Not marked complete · Included · Practice check available
Lesson preview
How often does an average miss the true value by more than your tolerance?
Original synthetic scenario. Every independent instrument reading measures a true value of 10 plus bias and one of five equally likely disturbances. Exact enumeration counts all possible sample sequences.
Same people, different order
○ Not marked complete · Included · Practice check available
Lesson preview
Does comparing each participant with themselves remove every bias?
Original synthetic scenario. Six fictional participants try methods A and B. Stable baseline scores differ; practice in the second period changes performance.
Design tests that reveal mechanisms
Use factorial conditions and discriminating inputs to test more than a favored explanation.
When two improvements cancel each other
○ Not marked complete · Included · Practice check available
Lesson preview
Is the effect of one intervention independent of the other?
Original synthetic scenario. Two fictional process changes A and B alter a 40-point baseline. You control the individual effects and their interaction.
Choose the test that could prove you wrong
○ Not marked complete · Included · Practice check available
Lesson preview
Where should you measure next when two explanations fit the existing observations?
Original synthetic scenario. Two candidate mechanisms agree at inputs zero and one. One grows linearly; the other curves upward. A selectable synthetic truth produces a new observation.
Control the outcome search
Distinguish a predeclared confirmatory test from an exploratory search and account for false alarms.
Search enough outcomes and find a surprise
○ Not marked complete · Included · Practice check available
Lesson preview
How does an outcome search change the chance of a false alarm?
Original synthetic scenario. Every candidate effect is absent. Independent tests nevertheless sometimes flag an effect, at a probability you choose.
Design and challenge an intervention study
Investigate whether a proposed study or process improvement produces a meaningful benefit. Use contrasting captures from at least two experiments, then specify a new investigation whose result could contradict your favored explanation. Deliver a protocol and a qualified conclusion; this workbench does not execute a real human study or certify its causal validity.
Save a report, compare captured evidence, and attempt three new cases. A completed report records submitted work; the rubric supports a separate human review of its quality.
Loading saved experiments…
Progress is saved in this browser when storage is available. Review your experiments and export a backup in My Work.
The complete science roadmap
The inquiry sequence and 28 biology lessons are available. Chemistry has 46 lessons and Physics has 123 lessons. 116 Earth and space science lessons explore Earth history, changing systems, orbital geometry and stellar evidence. 27 environmental science lessons explore water allocation, biodiversity evidence, nitrogen, land constraints, pollutant pathways, energy systems and urban decisions. The environmental cumulative project and twelve practice cases are available. Engineering has 23 lessons on measurable constraints, calibration, matched thermal prototypes, circuit diagnosis, sampled feedback and bounded reliability/tradeoff analysis, with a cumulative device-model report and twelve public practice cases. Each course describes its authored scope and evidence limits; an available lesson is not awarded completion credit. AP preparation is not AP authorization or college credit.
High-school foundations
Scientific inquiry and measurement
Role: a short entry course and a reusable strand throughout all science courses. Preparation: arithmetic, percentages and graph reading. Learners may use readiness checks and enter a subject directly rather than complete this course first.
Open lessons and investigationsBiology and living systems
Preparation: HS01 skills and basic chemical ideas introduced in context. Outcome: explain life from molecules to ecosystems using mechanisms, inheritance and evolutionary evidence.
Open biology lessonsChemistry and matter
Preparation: algebraic substitution, ratios, units and HS01 measurement. Outcome: connect observable properties to particle models and quantitative conservation.
Open chemistry lessonsPhysics and physical systems
Preparation: algebra, graph slopes and basic geometry; vectors and trigonometry introduced when needed. Outcome: explain and predict motion, energy transfer and interactions across representations.
Open physics lessonsEarth and space science
Preparation: HS01 skills; chemistry and physics concepts supplied locally. Outcome: explain Earth and space using observations over different spatial and temporal scales.
Open Earth and space science lessonsEnvironmental science and sustainability
Preparation: basic biology, matter/energy ideas and proportional reasoning. Outcome: evaluate environmental systems and interventions while separating physical evidence, uncertainty and value choices.
Open environmental science lessonsEngineering design and scientific computing
Role: a semester elective and an applied strand supporting the sciences. Preparation: HS01 and a relevant physical or life-science foundation. No programming required initially; a coding extension develops implementation competence separately.
Open engineering foundationsAP natural science
AP Biology
Preparation: high-school biology and chemistry. College Board describes a two-semester introductory biology scope. The eight content areas cover molecular foundations, cells, metabolism, cellular signaling/division, inheritance, regulation of genetic information, evolution and ecology. Official AP Biology scope.
Open AP Biology preparationAP Chemistry
Preparation: high-school chemistry and Algebra II. The framework spans atomic properties, bonding/structure, bulk materials and mixtures, reactions, kinetics, thermochemistry, equilibrium, acid/base chemistry and thermodynamic applications. Official AP Chemistry scope.
Open AP Chemistry preparationAP Physics 1
Preparation: algebra and geometry, with concurrent or prior Algebra II as a readiness target. Cover translation, forces, energy, momentum, rotational dynamics, rotational conservation, oscillation and fluids. In the current sequence, fluids belongs here. College Board Physics 1 and 2 overview.
Open implemented course categoriesAP Physics 2
Preparation: introductory mechanics and confident algebra/trigonometry. Cover thermal systems, electrostatic interactions and potential, circuits, magnetic phenomena, image formation, wave/optical effects and modern physics. Preserve its separation from the first course rather than using an obsolete fluids placement. Official AP Physics 2 course.
Open implemented course categoriesAP Physics C Mechanics
Preparation: calculus completed or concurrent, plus vector reasoning. The current seven-unit sequence treats translation, force, energy, momentum, rotational dynamics, rotational conservation and oscillation using calculus. Official AP Physics C Mechanics scope.
Open implemented course categoriesAP Physics C Electricity and Magnetism
Preparation: calculus-based mechanics and concurrent or prior calculus. Cover electric charge/field/flux, potential, conductors and capacitors, circuits, magnetic fields and induction. Official AP Physics C Electricity and Magnetism scope.
Open implemented course categoriesAP Environmental Science
Preparation: life and physical science laboratory experience plus algebra. Cover ecosystems, biodiversity, populations, Earth resources, land/water use, energy, air pollution, land/water pollution and global environmental change. Official AP Environmental Science scope and preparation.
Open implemented course categoriesIntroductory college science
General Biology I
Preparation: high-school biology and chemistry, or a targeted bridge. Modules: (1) scientific evidence and biological chemistry; (2) cells, microscopy and membranes; (3) enzymes, respiration and photosynthesis; (4) signaling and cell division; (5) Mendelian and chromosomal inheritance; (6) molecular genetics, regulation and introductory biotechnology.
Open implemented course categoriesGeneral Biology II
Preparation: SC01 or equivalent. Modules: (1) evolution and population genetics; (2) phylogenetics and biodiversity; (3) microbes, fungi and ecological roles; (4) plant structure, development and transport; (5) animal organization, regulation and comparative physiology; (6) behavior, populations, communities and ecosystems.
Open implemented course categoriesGeneral Chemistry I
Preparation: high-school chemistry and algebra. Modules: (1) measurement and chemical accounting; (2) atoms and electronic structure; (3) periodic properties and bonding; (4) molecular geometry and intermolecular interactions; (5) stoichiometry, solutions and gases; (6) thermochemistry and material properties.
Open implemented course categoriesGeneral Chemistry II
Preparation: SC03. Modules: (1) solution behavior and colligative properties; (2) kinetics and mechanisms; (3) chemical equilibrium; (4) acids, bases, buffers and titrations; (5) solubility and coupled equilibria; (6) entropy, free energy and electrochemistry, with introductory nuclear/coordination topics as the selected syllabus requires.
Open implemented course categoriesCollege Physics I with algebra
Preparation: algebra and trigonometry. Modules: (1) vectors and motion; (2) Newtonian dynamics; (3) work, energy and momentum; (4) rotation and equilibrium; (5) fluids; (6) thermal systems, oscillations and introductory waves.
Open implemented course categoriesCollege Physics II with algebra
Preparation: SC05. Modules: (1) charge, fields and potential; (2) DC circuits and electrical energy; (3) magnetism and induction; (4) waves, sound and interference; (5) geometrical and physical optics; (6) introductory atomic, quantum and nuclear physics.
Open implemented course categoriesUniversity Physics I with calculus
Preparation: concurrent Calculus I, vectors and trigonometry. Modules: (1) differential and integral kinematics; (2) forces and differential models; (3) work and energy; (4) momentum and extended systems; (5) rotation, gravitation and orbital motion; (6) oscillations, mechanical waves and fluids.
Open implemented course categoriesUniversity Physics II with calculus
Preparation: SC07 and integration skills; vector-field concepts taught in context. Modules: (1) continuous charge distributions; (2) flux, symmetry and potential; (3) conductors, capacitance and energy; (4) currents and circuit dynamics; (5) magnetic fields and forces; (6) induction, oscillating circuits and electromagnetic waves.
Open implemented course categoriesUniversity Physics III with calculus
Preparation: SC07–SC08 and calculus. Modules: (1) kinetic theory and thermodynamics; (2) entropy and thermal processes; (3) wave optics and imaging; (4) special relativity; (5) quantum evidence and introductory wave mechanics; (6) atoms, solids and nuclear processes.
Open implemented course categoriesPhysical geology and Earth systems
Preparation: introductory physical science and graph reading. Modules: (1) minerals, rocks and material processes; (2) geologic time and stratigraphy; (3) plate tectonics and Earth's interior; (4) deformation, earthquakes and volcanoes; (5) rivers, groundwater, glaciers and coasts; (6) resources, hazards and environmental change.
Open implemented course categoriesIntroductory astronomy
Preparation: algebra, ratios and introductory physical science. Modules: (1) sky geometry and observation; (2) gravity and orbital systems; (3) light, spectra and telescopes; (4) planets and planetary formation; (5) stars and stellar evolution; (6) galaxies, distances and cosmological evidence.
Open implemented course categoriesEnvironmental science and ecological systems
Preparation: introductory biology, chemistry and algebra, with bridges available. Modules: (1) systems, ecological processes and scale; (2) population/biodiversity measurement; (3) Earth resources and biogeochemical budgets; (4) energy, agriculture and water; (5) pollution and climate evidence; (6) intervention design, uncertainty and monitoring.
Open implemented course categoriesHuman anatomy and physiology foundations
Preparation: SC01-level cells and basic chemistry. Modules: (1) tissues and organization; (2) integument, skeleton and muscle; (3) nervous/endocrine regulation; (4) circulation, respiration and transport; (5) digestion, metabolism, renal regulation and fluid balance; (6) immunity, reproduction and integrated homeostasis.
Open implemented course categoriesIntroductory microbiology
Preparation: SC01 and basic chemistry. Modules: (1) microbial diversity and microscopy; (2) growth, metabolism and environmental conditions; (3) microbial genetics and gene transfer; (4) microbial ecology and useful applications; (5) host interactions and immunity; (6) control methods, resistance and interpretation of evidence.
Open implemented course categoriesScience storage: loading. No account or remote computation is required.