231 topics
Science
231 science topics written in plain English for K-5 readers, with facts you can trace to a source.
- Absolute error Grades 4-5 · 246 words · simpler version
- Acceleration Grades 2-3 · 595 words
- Accumulated error Grades 2-3 · 169 words · simpler version
- Accuracy and precision Grades 4-5 · 321 words · simpler version
- Acetone Grades 2-3 · 120 words
- Actinium Grades 2-3 · 266 words
- Alkali Grades 3-4 · 340 words
- Alkane Grades 4-5 · 405 words
- Aluminum Grades 3-4 · 1925 words · simpler version
- Americium Grades 3-4 · 302 words
- Anion Grades 3-4 · 326 words
- Antimatter Grades 4-5 · 1512 words
- Antimony Grades 2-3 · 993 words · simpler version
- Antioxidant Grades 3-4 · 123 words
- Approximation of numbers Grades 3-4 · 772 words · simpler version
- Argon Grades 2-3 · 418 words · simpler version
- Arsenic Grades 2-3 · 1097 words · simpler version
- Atom Grades 3-4 · 3831 words
- Barium Grades 2-3 · 615 words · simpler version
- Beryllium Grades 2-3 · 258 words · simpler version
- Bicarbonate and vinegar Grades 4-5 · 406 words · simpler version
- Bioluminescence Grades 4-5 · 858 words
- Biomass Grades 4-5 · 522 words
- Bismuth Grades 2-3 · 907 words · simpler version
- Boiling Grades 4-5 · 649 words
- Bonding Grades 4-5 · 716 words · simpler version
- Boron Grades 2-3 · 198 words · simpler version
- Bose-Einstein condensates Grades 4-5 · 835 words · simpler version
- Bromine Grades 2-3 · 468 words · simpler version
- Brownian motion Grades 4-5 · 593 words · simpler version
- Butane Grades 2-3 · 142 words
- Cadmium Grades 2-3 · 619 words
- Calcium Grades 4-5 · 1660 words · simpler version
- Carbon Grades 2-3 · 683 words · simpler version
- Celsius Grades 4-5 · 1082 words
- Cerium Grades 4-5 · 359 words · simpler version
- Cesium Grades 2-3 · 396 words · simpler version
- Chemistry Grades 3-4 · 18421 words
- Chiller Grades 3-4 · 373 words
- Chlorine Grades 2-3 · 824 words · simpler version
- Choline Grades 2-3 · 219 words
- Chromatography Grades 4-5 · 961 words
- Cobalt Grades 2-3 · 409 words · simpler version
- Colloid Grades 4-5 · 727 words
- Copernicium Grades 2-3 · 189 words
- Copper Grades 2-3 · 1122 words · simpler version
- Creatine Grades 4-5 · 306 words
- Crystallization Grades 3-4 · 446 words
- Darmstadtium Grades 2-3 · 280 words
- Density Grades 4-5 · 335 words
- Diffusion Grades 4-5 · 433 words · simpler version
- Distillation Grades 3-4 · 276 words
- Einsteinium Grades 3-4 · 137 words · simpler version
- Electromagnetism Grades 4-5 · 1267 words
- Electron Grades 3-4 · 1029 words
- Electronegativity Grades 3-4 · 518 words
- Electrostatics Grades 2-3 · 279 words
- Elements Grades 4-5 · 76 words · simpler version
- Energy Grades 4-5 · 634 words
- Entropy Grades 4-5 · 325 words
- Equilibrium Grades 4-5 · 524 words
- Errors Grades 4-5 · 386 words · simpler version
- Estimation in calculation Grades 4-5 · 294 words · simpler version
- Ethanol Grades 4-5 · 216 words
- Expand or contract? Grades 2-3 · 397 words · simpler version
- Explosive foam Grades 4-5 · 283 words · simpler version
- Final quiz Grades 2-3 · 174 words · simpler version
- Flerovium Grades 3-4 · 326 words
- Float or sink? Grades 3-4 · 1109 words · simpler version
- Fluorine Grades 2-3 · 559 words · simpler version
- Force Grades 4-5 · 656 words
- Francium Grades 2-3 · 299 words · simpler version
- Freezing Grades 4-5 · 627 words
- Frequency Grades 4-5 · 430 words
- Gallium Grades 2-3 · 154 words · simpler version
- Gas pressure Grades 2-3 · 535 words · simpler version
- Gases Grades 3-4 · 1402 words · simpler version
- Gasoline Grades 2-3 · 798 words
- Geophysics Grades 3-4 · 258 words
- Gold Grades 3-4 · 1154 words · simpler version
- Gravity Grades 3-4 · 1221 words
- Grow your own crystals Grades 3-4 · 792 words · simpler version
- Grow your own fungi Grades 3-4 · 270 words · simpler version
- Hadron Grades 3-4 · 267 words
- Half-life Grades 3-4 · 330 words
- Hassium Grades 2-3 · 240 words
- Heat Grades 4-5 · 410 words
- Helium Grades 3-4 · 742 words · simpler version
- Holography Grades 4-5 · 806 words
- How A Bath Fizzer Works, and How To Make One Grades 4-5 · 332 words · simpler version
- How to make a needle float, and how to make it sink Grades 4-5 · 482 words · simpler version
- How to Make an Electromagnet Grades 3-4 · 299 words · simpler version
- Hydrogen Grades 3-4 · 2959 words · simpler version
- Introduction to The Elements Grades 3-4 · 439 words · simpler version
- Iodine Grades 2-3 · 1301 words · simpler version
- Ionization Grades 4-5 · 787 words
- Iron Grades 2-3 · 1530 words · simpler version
- Isoprene Grades 2-3 · 197 words
- Isotope Grades 3-4 · 828 words
- Joule Grades 4-5 · 336 words
- Kelvin Grades 3-4 · 364 words
- Krypton Grades 2-3 · 297 words · simpler version
- Lead Grades 2-3 · 966 words · simpler version
- Light Grades 2-3 · 961 words
- Lightning Grades 3-4 · 285 words
- Liquids Grades 3-4 · 241 words · simpler version
- Lithium Grades 2-3 · 1086 words · simpler version
- Louver Grades 3-4 · 340 words
- Magnesium Grades 3-4 · 608 words · simpler version
- Magnet Grades 3-4 · 520 words
- Magnetism Grades 3-4 · 824 words
- Manganese Grades 2-3 · 860 words · simpler version
- Mass Grades 4-5 · 580 words
- Matter Grades 4-5 · 689 words · simpler version
- Matter Is The Stuff Around You Grades 2-3 · 359 words · simpler version
- Measurement Grades 2-3 · 414 words · simpler version
- Metallurgy Grades 2-3 · 915 words
- Methane Grades 3-4 · 140 words
- Microwave Grades 4-5 · 280 words
- Mixtures Grades 3-4 · 190 words · simpler version
- Molecule Grades 3-4 · 415 words
- Momentum Grades 4-5 · 620 words
- Moscovium Grades 3-4 · 401 words
- Movement Grades 3-4 · 595 words
- Multiverse Grades 3-4 · 148 words
- Naphthalene Grades 2-3 · 147 words
- Neodymium Grades 3-4 · 294 words · simpler version
- Neon Grades 3-4 · 307 words · simpler version
- Neptunium Grades 4-5 · 214 words · simpler version
- Neutrino Grades 4-5 · 477 words
- Neutron Grades 2-3 · 305 words
- Nickel Grades 2-3 · 874 words · simpler version
- Nihonium Grades 2-3 · 243 words
- Niobium Grades 2-3 · 334 words
- Nitrogen Grades 2-3 · 727 words · simpler version
- Noise Grades 3-4 · 218 words
- Odor Grades 4-5 · 403 words
- Oganesson Grades 4-5 · 367 words · simpler version
- Oobleck Grades 2-3 · 129 words · simpler version
- Overview Grades 2-3 · 265 words · simpler version
- Oxygen Grades 3-4 · 3425 words · simpler version
- Ozone Grades 2-3 · 253 words
- Particle model Grades 3-4 · 344 words · simpler version
- Particle theory Grades 3-4 · 313 words · simpler version
- Periodic Table Grades 4-5 · 716 words · simpler version
- PH Grades 4-5 · 396 words
- Phosgene Grades 2-3 · 260 words
- Phosphorus Grades 2-3 · 644 words · simpler version
- Photon Grades 3-4 · 671 words
- Physics Grades 4-5 · 2498 words
- Pinhole Camera Grades 4-5 · 254 words · simpler version
- Plasma Grades 4-5 · 18 words · simpler version
- Plastic Grades 3-4 · 819 words
- Platinum Grades 2-3 · 282 words · simpler version
- Plutonium Grades 3-4 · 272 words · simpler version
- Polarization Grades 4-5 · 803 words
- Polonium Grades 3-4 · 238 words · simpler version
- Polyester Grades 2-3 · 254 words
- Polymer Grades 3-4 · 315 words
- Potassium Grades 2-3 · 717 words · simpler version
- Promethium Grades 3-4 · 97 words · simpler version
- Quasiparticle Grades 4-5 · 132 words
- Radiation Grades 3-4 · 699 words
- Radium Grades 3-4 · 597 words · simpler version
- Radon Grades 3-4 · 287 words · simpler version
- Rainbow columns Grades 3-4 · 251 words · simpler version
- Rare Elements Grades 2-3 · 4657 words · simpler version
- Red cabbage indicator Grades 3-4 · 652 words · simpler version
- Redox Grades 4-5 · 259 words
- Rotation Grades 3-4 · 253 words
- Rubidium Grades 2-3 · 420 words · simpler version
- Rutherfordium Grades 3-4 · 346 words
- Scalar Grades 4-5 · 294 words
- Scandium Grades 2-3 · 131 words · simpler version
- Seaborgium Grades 2-3 · 197 words
- Shakti Grades 4-5 · 656 words
- Silicate Grades 3-4 · 390 words
- Silicon Grades 2-3 · 234 words · simpler version
- Silver Grades 2-3 · 760 words · simpler version
- Sky Grades 3-4 · 262 words
- Slime Grades 3-4 · 289 words · simpler version
- Soap powered boat Grades 4-5 · 321 words · simpler version
- Sodium Grades 4-5 · 638 words · simpler version
- Solids Grades 3-4 · 419 words · simpler version
- Solutions Grades 3-4 · 182 words · simpler version
- Solvent Grades 4-5 · 1040 words
- Sound Grades 2-3 · 755 words
- Spacetime Grades 3-4 · 540 words
- Spectroscopy Grades 3-4 · 459 words
- Spectrum Grades 4-5 · 289 words
- Speed Grades 2-3 · 243 words
- States Of Matter Grades 3-4 · 1047 words · simpler version
- Stereochemistry Grades 3-4 · 576 words
- Strange Element Grades 2-3 · 189 words · simpler version
- Strontium Grades 2-3 · 153 words · simpler version
- Structure Grades 2-3 · 60 words · simpler version
- Substance Grades 4-5 · 399 words
- Sulfur Grades 4-5 · 703 words · simpler version
- Summary Grades 2-3 · 164 words · simpler version
- Superconductor Grades 4-5 · 408 words
- Taurine Grades 2-3 · 124 words
- Tellurium Grades 2-3 · 753 words · simpler version
- Temperature Grades 3-4 · 591 words
- Tetrahydrocannabinol Grades 4-5 · 551 words
- Thallium Grades 2-3 · 773 words · simpler version
- Thermochemistry Grades 3-4 · 570 words
- Thermometer Grades 4-5 · 420 words
- Thermoplastic Grades 3-4 · 382 words
- Thorium Grades 2-3 · 233 words
- Thrust Grades 4-5 · 741 words
- Tin Grades 2-3 · 832 words · simpler version
- Titanium Grades 4-5 · 262 words · simpler version
- Torque Grades 4-5 · 329 words
- Transformer Grades 4-5 · 363 words
- Tungsten Grades 2-3 · 178 words · simpler version
- Ultrasound Grades 4-5 · 495 words
- Uranium Grades 2-3 · 636 words · simpler version
- Urea Grades 4-5 · 121 words
- Van Grades 4-5 · 2164 words
- Vanadium Grades 2-3 · 406 words · simpler version
- Vector Grades 4-5 · 765 words
- Velocity Grades 4-5 · 489 words
- Volt Grades 4-5 · 473 words
- Voltage Grades 4-5 · 1134 words
- Water Grades 3-4 · 24088 words
- Weight Grades 4-5 · 713 words
- What's a molecule? Grades 4-5 · 370 words · simpler version
- Why does it rain? Grades 3-4 · 394 words · simpler version
- Windmill Grades 2-3 · 521 words
- X-ray Grades 2-3 · 410 words
- Zinc Grades 2-3 · 1612 words · simpler version
Articles in Learn are adapted from Simple English Wikipedia and Wikijunior by their contributors, and are published under CC BY-SA 4.0. Each article names its source and links to it. See credits.