80 Smart Science Riddles For Kids & Adults

These fun science riddles will tickle your brain, spark curiosity, and help kids and adults alike learn in a clever way. Great for classrooms, science clubs, or casual fun!


Physics Riddles

  1. I can go up and down but never move. What am I?

Answer: Temperature


  1. I fall but never rise. What am I?

Answer: Rain


  1. The faster you go, the more I push against you. What am I?

Answer: Air resistance


  1. I have energy but no mass. What am I?

Answer: Light


  1. I’m not alive, but I grow. I don’t breathe, but I blow. What am I?

Answer: Crystal


  1. I make things float or sink. What am I?

Answer: Buoyancy


  1. I’m invisible, yet I hold things down. What am I?

Answer: Gravity


  1. I’m measured in Newtons. What am I?

Answer: Force


  1. I can vibrate, echo, and bounce. What am I?

Answer: Sound


  1. The more I vibrate, the higher I sound. What am I?

Answer: Frequency


  1. I’m created when energy changes forms. What am I?

Answer: Heat


  1. I flow through wires and light your world. What am I?

Answer: Electricity


  1. I move fast in a vacuum and slow in water. What am I?

Answer: Light


  1. I go through walls but bounce off metal. What am I?

Answer: Magnetic field


  1. I measure motion, not distance. What am I?

Answer: Speed


  1. I resist change, especially in motion. What am I?

Answer: Inertia


  1. I’m the reason you feel heavy or light. What am I?

Answer: Gravity


  1. I reflect, absorb, or pass through. What am I?

Answer: Light


  1. Without me, you’d float into space. What am I?

Answer: Gravity


  1. I expand when heated and contract when cooled. What am I?

Answer: Matter


Chemistry Riddles

  1. I bubble and fizz when mixed. What am I?

Answer: Chemical reaction


  1. I’m the smallest part of a compound. What am I?

Answer: Molecule


  1. I change colors but I’m not magic. What am I?

Answer: Indicator


  1. I’m used to test acids and bases. What am I?

Answer: Litmus paper


  1. I’m solid, liquid, and gas. What am I?

Answer: Matter


  1. I can bond, break, or explode. What am I?

Answer: Atom


  1. I’m salty but not food. What am I?

Answer: Sodium


  1. I freeze at 0°C and boil at 100°C. What am I?

Answer: Water


  1. I’m the gas you breathe out. What am I?

Answer: Carbon dioxide


  1. I’m used to clean, but I’m a compound. What am I?

Answer: Soap


  1. I rust metal but help plants. What am I?

Answer: Oxygen


  1. I’m slippery, sour, or bitter. What am I?

Answer: Chemical


  1. I explode with vinegar. What am I?

Answer: Baking soda


  1. I’m not alive, but I react. What am I?

Answer: Chemical substance


  1. I have protons, neutrons, and electrons. What am I?

Answer: Atom


  1. I change forms but never disappear. What am I?

Answer: Matter


  1. I’m found on the periodic table and love bonding. What am I?

Answer: Element


  1. I give off heat when I react. What am I?

Answer: Exothermic reaction


  1. I hide inside water, but I’m a gas. What am I?

Answer: Hydrogen


  1. I cause things to burn. What am I?

Answer: Oxygen


Biology Riddles

  1. I’m in your blood but not your bones. What am I?

Answer: Plasma


  1. I help you breathe but I’m not your nose. What am I?

Answer: Lungs


  1. I carry oxygen around your body. What am I?

Answer: Red blood cells


  1. I digest but I’m not hungry. What am I?

Answer: Stomach


  1. I connect bones together. What am I?

Answer: Ligament


  1. I pump and never stop. What am I?

Answer: Heart


  1. I make food for plants. What am I?

Answer: Chloroplast


  1. I absorb water from the ground. What am I?

Answer: Roots


  1. I’m the brain of a plant cell. What am I?

Answer: Nucleus


  1. I keep cells in shape. What am I?

Answer: Cell wall


  1. I’m the powerhouse of the cell. What am I?

Answer: Mitochondria


  1. I protect your body from germs. What am I?

Answer: Immune system


  1. I grow hair and nails. What am I?

Answer: Skin


  1. I’m green and love sunlight. What am I?

Answer: Leaf


  1. I stretch, flex, and help you move. What am I?

Answer: Muscle


  1. I’m made of cells but I’m not a jail. What am I?

Answer: Tissue


  1. I beat faster when you run. What am I?

Answer: Heart


  1. I see but have no eyes. What am I?

Answer: Microscope


  1. I carry messages in your body. What am I?

Answer: Nerves


  1. I’m part of DNA and shape who you are. What am I?

Answer: Genes


General Science Riddles

  1. I orbit the Sun and reflect light. What am I?

Answer: Planet


  1. I’m hot, bright, and center of the system. What am I?

Answer: Sun


  1. I shine at night but don’t make my own light. What am I?

Answer: Moon


  1. I’m full of stars and galaxies. What am I?

Answer: Universe


  1. I bring thunder, lightning, and rain. What am I?

Answer: Storm


  1. I fall from the sky and make things wet. What am I?

Answer: Rain


  1. I freeze everything and form snow. What am I?

Answer: Cold


  1. I warm the Earth but can burn your skin. What am I?

Answer: Sunlight


  1. I happen when tectonic plates move. What am I?

Answer: Earthquake


  1. I cause volcanoes to erupt. What am I?

Answer: Magma


  1. I go up as heat increases. What am I?

Answer: Thermometer


  1. I circle Earth and help forecast weather. What am I?

Answer: Satellite


  1. I orbit Earth and affect tides. What am I?

Answer: Moon


  1. I measure distance in space. What am I?

Answer: Light-year


  1. I am both a solid and a crystal. What am I?

Answer: Ice


  1. I store energy and make devices work. What am I?

Answer: Battery


  1. I measure mass, not weight. What am I?

Answer: Balance scale


  1. I’m a tool with lenses that makes things closer. What am I?

Answer: Telescope


  1. I help you zoom into tiny life. What am I?

Answer: Microscope


  1. I record temperature and help forecast. What am I?

Answer: Thermometer

Similar Posts