Why Is the Sky Blue?
The biggest questions often have the most beautiful answers.
The Daily Lesson™ — 365 Days of Learning
A new lesson every day, personalized to your age, language, and how you learn best. Available in 47+ languages for learners ages 2-102.
365 lessons47+ languagesAges 2-1025 learning phases
January
Physics
Why the Sky is Blue
Learn why our sky appears blue during the day.
How Birds Fly
Discover the secrets of bird flight.
The Moon and Its Phases
Understand why the moon appears to change shape.
Where Rain Comes From
Follow the journey of a raindrop.
Why Leaves Change Color
Learn the science behind autumn colors.
How Seeds Grow
Watch the miracle of seeds becoming plants.
Why We Dream
Explore the mysterious world of dreams.
How Rainbows Form
Discover the science behind rainbows.
Why Dogs Wag Their Tails
Decode the secret language of dog tails.
The Secret Life of Ants
Discover the incredible strength of tiny ants.
Why Stars Twinkle
Learn why stars appear to twinkle in the night sky.
How Butterflies Transform
Follow the amazing journey from caterpillar to butterfly.
Why the Ocean is Salty
Discover why ocean water tastes salty.
How Bees Make Honey
Follow the journey from flower nectar to golden honey.
Why We Get Goosebumps
Learn why we still get goosebumps today.
How Volcanoes Erupt
Explore what happens inside an erupting volcano.
Why Cats Purr
Discover the surprising reasons cats purr.
How Magnets Work
Explore the invisible power of magnets.
Why We Yawn
Learn the surprising science behind yawning.
How Fish Breathe Underwater
Discover how fish breathe without air.
Why Ice Floats
Learn why ice floating is important for life on Earth.
How Spiders Make Webs
Marvel at the engineering of spider webs.
Why We Have Fingerprints
Explore why fingerprints make you unique.
How Thunder and Lightning Happen
Learn what causes thunder and lightning.
Why Leaves are Green
Discover why plants chose the color green.
How Owls See in the Dark
Learn the secrets of owl night vision.
Why We Get Hiccups
Understand the science behind hiccups.
How Chameleons Change Color
Discover how chameleons become masters of disguise.
Why the Sun Sets Red
Learn why sunsets paint the sky in warm colors.
How Earthworms Help Gardens
Discover why gardeners love earthworms.
February
Why Soap Makes Bubbles
Learn the science behind beautiful bubbles.
How Planes Stay Up
Discover how airplanes defy gravity.
Why Popcorn Pops
Uncover the explosive science of popcorn.
How Dolphins Sleep
Learn how dolphins nap without drowning.
Why We Sneeze
Discover the explosive purpose of sneezing.
How Mirrors Work
Understand the optics behind mirrors.
Why Flamingos are Pink
Learn why flamingos owe their color to dinner.
How Glow Sticks Glow
Discover the chemistry behind glow sticks.
Why Onions Make You Cry
Learn why onions attack your eyes.
How Seeds Travel
Explore the adventures of traveling seeds.
Why We Get Dizzy
Understand why spinning makes you wobbly.
How Whales Sing
Discover the haunting music of whales.
Why Hair Turns Gray
Learn why hair loses its color over time.
How Fireflies Light Up
Uncover the glowing secret of fireflies.
Why Bananas Bruise
Discover why bananas wear their bruises.
How Glaciers Move
Learn how massive ice rivers shape the land.
Why Leaves Float Down Slowly
Understand why leaves take their time falling.
How Elephants Remember
Explore the incredible memory of elephants.
Why the Sea Has Waves
Discover the wind-powered engine of ocean waves.
How Frogs Jump So Far
Discover the secret springs in frog legs.
Why We Shiver When Cold
Learn why shaking keeps you warm.
How Camels Survive Deserts
Explore the desert survival kit of camels.
Why Balloons Float
Understand why some balloons float away.
How Bats See in the Dark
Discover how bats navigate with sound.
Why Pepper Makes You Sneeze
Learn why pepper attacks your nose.
How Penguins Stay Warm
Explore how penguins beat the cold.
Why Clocks Go Clockwise
Discover the sunny origin of clockwise.
How Octopuses Change Shape
Marvel at the boneless wonder of octopuses.
Why Paper Cuts Hurt So Much
Understand the intense pain of paper cuts.
March
How Hummingbirds Hover
Discover the incredible hovering of hummingbirds.
Why Apples Turn Brown
Learn why apples rust like metal.
How Sharks Smell Blood
Explore the incredible nose of sharks.
Why the Wind Blows
Understand the engine that drives the wind.
How Snakes Slither
Discover the legless locomotion of snakes.
Why Ice Cream Gives Brain Freeze
Learn why cold treats can cause head pain.
How Coral Reefs Grow
Discover the living cities of coral reefs.
Why Knuckles Crack
Understand the bubble-pop of cracking joints.
How Cacti Store Water
Explore the water-saving secrets of cacti.
Why We Blink
Learn why we blink 15000 times a day.
How Turtles Carry Their Homes
Discover why turtles are born with built-in protection.
Why Music Makes Us Happy
Learn why music affects our emotions.
How Jellyfish Move
Explore the pulsing propulsion of jellyfish.
Why Hot Air Rises
Understand why warmth always rises.
How Sloths Move So Slowly
Discover why sloths take life easy.
Why Static Makes Hair Stand Up
Learn why static electricity makes hair wild.
How Woodpeckers Dont Get Headaches
Explore the shock-absorbing head of woodpeckers.
Why We See Colors
Discover how eyes detect the rainbow.
How Starfish Regrow Arms
Marvel at the regenerating starfish.
Why Cuts Bleed Then Stop
Learn how blood seals itself.
How Giraffes Drink Water
Discover the engineering of giraffe necks.
Why Old Books Smell
Explore the chemistry of book smell.
How Salmon Find Their Way Home
Follow the nose of the wandering salmon.
Why Wheels Roll
Understand why the wheel changed everything.
How Crocodiles Hold Their Breath
Discover the diving secrets of crocodiles.
Why Eggs Are Egg-Shaped
Learn why eggs have their unique shape.
How Plants Know Which Way Is Up
Discover how plants sense gravity.
Why Chili Peppers Are Hot
Explore the fake fire of chili peppers.
How Echoes Work
Understand how sound bounces back.
Why Some Animals Play Dead
Learn why faking death saves lives.
How Diamonds Form
Discover the deep origins of diamonds.
April
Why Cats Land on Their Feet
Explore the acrobatic reflexes of cats.
How Fossils Form
Follow a creature from life to fossil.
Why Mosquito Bites Itch
Learn why bites trigger the scratch urge.
How Northern Lights Form
Witness the cosmic light show.
Why We Have Eyebrows
Discover the surprising uses of eyebrows.
How Electric Eels Shock
Explore the shocking biology of electric eels.
Why Shadows Change Size
See how light angle changes shadow size.
How Squirrels Remember Where They Buried Nuts
Discover the amazing memory of squirrels.
Why Hundred is Special
Explore why 100 marks a celebration.
How Rainbows Form
Discover how raindrops become prisms.
Why Dogs Wag Their Tails
Decode the language of dog tails.
How Clouds Float
Learn why clouds defy gravity.
Why We Have Different Blood Types
Explore the varieties of human blood.
How Kangaroos Jump
Discover the spring-loaded legs of kangaroos.
Why Teeth Fall Out
Understand why you get two sets of teeth.
How Seahorses Swim
Explore the unique swimming of seahorses.
Why We Get Hungry
Learn why empty stomachs make noise.
How Peacocks Fan Their Feathers
Marvel at the spectacular peacock display.
Why Water Puts Out Fire
Understand how water defeats fire.
How Parrots Talk
Discover how parrots master human speech.
Why Glass Is See-Through
Explore why glass is transparent.
How Beavers Build Dams
Discover the construction skills of beavers.
Why We Dream
Explore the mysterious world of dreams.
How Lizards Regrow Tails
Learn about the amazing regenerating lizard.
Why Soap Is Slippery
Understand the slippery science of soap.
How Owls Hunt Silently
Discover the silent flight of owls.
Why We Have Belly Buttons
Understand the origin of belly buttons.
How Hermit Crabs Find Homes
Follow the house-hunting hermit crab.
Why Metal Feels Cold
Learn why metal tricks your temperature sense.
How Cheetahs Run So Fast
Discover the speed machine of cheetahs.
May
Why Boats Float
Understand how ships defy sinking.
How Caterpillars Know When to Change
Explore the timing of metamorphosis.
Why We Have Two Eyes
Discover why two eyes are better.
How Mushrooms Grow Overnight
Understand the hidden life of fungi.
Why Rubber Bounces
Explore the springy science of rubber.
How Arctic Animals Stay White
Discover the color-changing arctic animals.
Why We Get Tired
Learn what makes sleep necessary.
How Geysers Erupt
Explore the explosive power of geysers.
Why Birds Migrate
Follow the incredible journeys of migrating birds.
How Taste Buds Work
Discover how your tongue detects flavors.
Why Trees Have Rings
Read the story told by tree rings.
How Polar Bears Stay Warm
Explore the winter survival of polar bears.
Why We Laugh
Understand the science of laughter.
How Spiders Dont Get Stuck
Discover how spiders master their webs.
Why Ice Is Slippery
Learn why ice is a slipping hazard.
How Seeds Know To Grow
Understand what triggers seed germination.
Why Flamingos Stand on One Leg
Discover the one-legged secret of flamingos.
How Crickets Make Music
Listen to the instruments of crickets.
Why Wounds Scab
Understand your bodys natural bandage.
How Tornadoes Form
Explore the birth of tornadoes.
Why Some Animals Are Nocturnal
Discover the advantages of nightlife.
How Coins Get Their Ridges
Learn the anti-theft history of coin edges.
Why We Get Bruises
Understand the rainbow of bruise colors.
How Skunks Spray
Explore the chemical weapon of skunks.
Why Flowers Are Colorful
Discover why flowers dress to impress.
How Compasses Point North
Understand the magnetic mystery of compasses.
Why We Get Wrinkly Fingers in Water
Discover the purpose of pruney fingers.
How Catfish Find Food in Murky Water
Explore the super senses of catfish.
Why Halfway Through the Year Matters
Celebrate reaching the middle of the journey.
How Ants Carry Heavy Things
Discover the superhuman strength of ants.
Why Yawning Is Contagious
Explore why yawns spread like wildfire.
June
How Volcanoes Erupt
Understand the explosive power of volcanoes.
Why We Have Fingerprints
Discover why fingerprints are one-of-a-kind.
How Chameleons Change Colors
Watch chameleons paint themselves.
Why We Get Goosebumps
Learn about the ancient reflex of goosebumps.
How Worms Eat Dirt
Follow a worms journey through the earth.
Why Hot Drinks Steam
Watch water jump between invisible and visible.
How Pigeons Find Their Way Home
Discover the GPS inside pigeons.
Why Feet Fall Asleep
Understand the pins and needles feeling.
How Butterflies Taste With Their Feet
Discover how butterflies sample the world.
Why Paper Is White
Explore why paper reflects all colors.
How Snails Make Slime
Slide along with snail slime science.
Why Lightning Zigzags
Follow the branching path of lightning.
How Crocodiles Cry
Understand the real reason crocodiles tear up.
Why Springs Bounce Back
Explore the stored energy in springs.
How Fish Breathe Underwater
Discover the underwater breathing of fish.
Why We Have Two Nostrils
Understand the teamwork of your nostrils.
How Dolphins Echolocate
Explore how dolphins see with sound.
Why Old Photos Turn Yellow
Watch chemistry age photographs.
How Venus Flytraps Catch Bugs
Discover the fastest moving plant.
Why We Have Eyelashes
Appreciate your built-in eye shields.
How Hot Air Balloons Float
Understand the simple physics of ballooning.
Why Some Animals Hibernate
Explore the deep sleep of hibernation.
How Magnets Work
Discover the invisible pull of magnets.
Why Spicy Food Makes You Sweat
Feel the heat of capsaicin trickery.
How Quicksand Works
Separate quicksand fact from fiction.
Why We Have Earwax
Appreciate your ears natural guardian.
How Porcupines Use Their Quills
Understand the prickly protection of porcupines.
Why Half a Year Matters
Celebrate six months around the sun.
How Sunflowers Follow the Sun
Follow the sun-chasing sunflower.
Why Helium Changes Your Voice
Discover why helium raises the pitch.
July
How Electric Cars Work
Explore the battery-powered future of cars.
Why Bees Make Honey
Follow nectars journey to honey.
How Tides Rise and Fall
Feel the moons pull on the oceans.
Why We Get Motion Sick
Understand the mixed-signal sickness.
How Pufferfish Puff Up
Watch the amazing inflation of pufferfish.
Why We Have Accents
Explore how accents develop and spread.
How Avalanches Start
Understand the chain reaction of avalanches.
Why Cats Purr
Listen to the mystery of the purr.
How Geckos Walk on Walls
Discover the atomic grip of gecko feet.
Why Leaves Turn Red and Yellow
Watch the chemistry of autumn unfold.
How Submarines Dive
Explore how submarines master depth.
Why Dominoes Fall in a Chain
Witness the energy transfer of dominoes.
How Sloths Grow Algae
Discover the living fur of sloths.
Why Bananas Are Curved
Follow the curve-creating growth of bananas.
How Cicadas Know When to Emerge
Marvel at the 17-year wait of cicadas.
Why Stars Twinkle
See through the illusion of twinkling.
How Quicksand Grips You
Understand the science of staying calm in quicksand.
Why 200 Days Feels Like an Achievement
Celebrate 200 days of growing wonder.
How Fireflies Light Up
Discover the chemical magic of firefly glow.
Why We Get Hiccups
Explore the jumpy diaphragm of hiccups.
How Glaciers Move
Watch mountains of ice slowly march.
Why We Have Baby Teeth
Understand the placeholder role of baby teeth.
How Camouflage Works
See how animals become invisible.
Why Onions Make You Cry
Understand the tear gas of onions.
How Elephants Communicate
Hear the ground-shaking calls of elephants.
Why Blood Is Red
Discover the iron that colors your blood.
How Roller Coasters Work
Ride the physics of roller coasters.
Why Wet Dogs Smell
Sniff out the science of wet dog smell.
How Seeds Travel
Follow the amazing journeys of seeds.
Why Hair Turns Gray
Understand why hair fades to gray.
How Antibiotics Fight Germs
Explore the germ-fighting power of antibiotics.
August
Why Cats Knead
Understand the happy kneading of cats.
How Mountains Form
Watch continents build mountains.
Why Soda Fizzes
Discover the bubbly science of carbonation.
How Owls Turn Their Heads
Marvel at the rotating head of owls.
Why We Get Sleepy After Eating
Understand the post-meal sleepiness.
How Planes Stay Up
Lift off with airplane physics.
Why Soap Bubbles Are Round
See why bubbles love being round.
How Spiders Spin Webs
Watch spiders engineer their homes.
Why Bones Are Hard
Discover the living fortress of bones.
How Earthquakes Happen
Feel why the earth shakes.
Why Popcorn Pops
Explode into the science of popcorn.
How Coral Changes Colors
Understand why coral loses its color.
Why We Have Different Eye Colors
See what paints your iris.
How Batteries Work
Unpack the chemistry inside batteries.
Why Dogs Circle Before Lying Down
Spin with the circling dog.
How Vaccines Train Your Body
Train your immune system with vaccines.
Why Honey Never Spoils
Discover honeys eternal freshness.
How Mirrors Reflect
See the physics behind mirrors.
Why Cats Hate Water
Splash into why cats stay dry.
How Clouds Form
Watch water vapor become clouds.
Why We Have Tonsils
Meet your throat guardians.
How Microwaves Heat Food
Vibrate into microwave science.
Why Flamingos Are Pink
Eat your way to understanding flamingo pink.
How Glow Sticks Glow
Mix chemicals to make glow.
Why Mosquitoes Bite Some People More
Sniff out why mosquitoes have favorites.
How Waterfalls Form
Watch rivers carve waterfalls.
Why We Have Nightmares
Face the purpose of nightmares.
How Whales Sing
Dive into the singing sea giants.
Why Grass Is Green
See why chlorophyll makes plants green.
How Quicksilver Flows
Flow with the liquid metal.
Why We Sweat When Nervous
Feel the stress response in your palms.
September
How Black Holes Work
Peer into the gravity monsters.
Why Some Wood Floats and Some Sinks
Weigh the density of different woods.
How Fingerprint Scanners Work
Map the technology of fingerprint scanners.
Why Plants Need Sleep Too
Tuck plants in for the night.
How Smell Triggers Memories
Sniff your way through memory lane.
Why 250 Days of Wonder
Celebrate over two-thirds of a year of wonder.
How Octopuses Have Three Hearts
Count the hearts of the octopus.
Why Paper Cuts Hurt So Much
Feel why paper cuts pack a punch.
How Hummingbirds Hover
Freeze-frame the hovering hummingbird.
Why Ice Floats
Float with the unusual ice.
How Touch Screens Know Your Finger
Tap into touchscreen technology.
Why Leaves Float Down Slowly
Drift with the falling leaves.
How Roosters Know When to Crow
Wake up with the clockwork rooster.
Why Knuckles Crack
Pop the mystery of knuckle cracking.
How Salmon Swim Upstream
Leap upstream with the salmon.
Why Salt Melts Ice
Dissolve the mystery of salt and ice.
How Monarch Butterflies Navigate
Follow the amazing monarch migration.
Why We Blush
Feel the heat of blushing.
How Raindrops Are Shaped
Reshape your idea of raindrops.
Why Dogs Have Wet Noses
Sniff out the purpose of wet noses.
How Wind Forms
Feel the pressure differences that make wind.
Why We Get Brain Freeze
Freeze into the brain freeze mystery.
How Coral Reefs Build Up
Build understanding of coral construction.
Why Wool Keeps You Warm When Wet
Stay warm with wonderful wool.
How Cacti Store Water
Store up cactus survival secrets.
Why We Get Deja Vu
Experience the mystery of deja vu.
How Woodpeckers Find Bugs
Tap into woodpecker hunting skills.
Why Rubber Bands Stretch
Stretch into rubber band science.
How 3D Movies Work
Pop into 3D movie magic.
Why Some People Are Left-Handed
Hands down explore handedness.
October
How Caves Form
Dissolve into cave formation.
Why Astronauts Float in Space
Float through the truth about space.
How Seeds Stay Dormant
Wake the sleeping seeds.
Why Metals Conduct Electricity
Conduct yourself through metal science.
How Pelicans Catch Fish
Scoop up pelican fishing secrets.
Why We Get Thirsty
Drink in the science of thirst.
How Homing Pigeons Return
Fly home with the homing pigeons.
Why Soap Makes Bubbles
Bubble up with soap science.
How Frogs Breathe Through Their Skin
Absorb the breathing secrets of frogs.
Why Elevators Have Mirrors
Reflect on elevator psychology.
How Sundials Tell Time
Track time with the ancient sundial.
Why We Get Car Sick Reading
Read into the motion sickness mystery.
How Kangaroos Keep Their Babies Safe
Hop into kangaroo parenting.
Why Glue Sticks
Stick with glue science.
How Seagulls Drink Salt Water
Filter through seagull secrets.
Why Old Apples Get Wrinkly
Witness the withering apple.
How Northern Animals Change Fur
Change colors with the seasons.
Why Candles Flicker
Flicker into candle flame physics.
How Earthworms Help Soil
Dig into earthworm benefits.
Why Hot Water Makes Steam
Steam into phase change science.
How Bats Use Sound
Echo into bat navigation.
Why Clothes Fade in Sunlight
Fade into the science of sun damage.
How Chameleon Tongues Work
Snap into chameleon tongue science.
Why We Get Wrinkles
Fold into wrinkle formation.
How Spiders Know When Prey Is Caught
Vibrate into spider sensing.
Why Day 300 Is a Milestone
Celebrate the 300-day milestone of wonder.
How Rainforests Make Their Own Rain
Discover how forests create their own rain.
Why We Sneeze in Sunlight
Brighten up to the sun-sneeze mystery.
How Lighthouses Guided Ships
Shine light on lighthouse history.
Why Tomatoes Are Fruits
Fruit out the truth about tomatoes.
How Armadillos Roll Into Balls
Roll with the armadillo defense.
November
Why Tape Sticks
Stick with tape science.
How Sharks Smell Blood
Sniff out the truth about shark noses.
Why We Have Dimples
Dent into dimple genetics.
How Quicksand Actually Works
Sink into quicksand facts.
Why Mirrors Flip Left and Right
Reflect on mirror mysteries.
How Fireproof Suits Work
Suit up with fireproof science.
Why Penguins Waddle
Waddle into penguin walking science.
How Coffee Keeps You Awake
Wake up to caffeine chemistry.
Why Knees Jerk at the Doctor
Kick into reflex science.
How Pearls Form
Layer into pearl formation.
Why We See Our Breath in Cold
Breathe out the visible breath mystery.
How Ants Survive Floods
Float with the incredible ant rafts.
Why Peppers Are Different Colors
Ripen into pepper colors.
How Pit Vipers See Heat
See heat with the pit vipers.
Why Aluminum Foil Has Two Sides
Unfold the foil manufacturing story.
How Camels Store Energy
Hump into the real camel story.
Why Salt Makes Food Taste Better
Season yourself with salt science.
How Cats Always Land on Their Feet
Flip into cat righting reflexes.
Why Some Mushrooms Glow
Glow with the magical mushrooms.
How Calculators Work
Calculate into electronic math.
Why Hazel Eyes Change Color
Shift into eye color science.
How Quickdrying Fabrics Work
Dry out with fabric engineering.
Why Woodlice Roll Into Balls
Roll with the pill bug defense.
How Northern Lights Sound
Listen to the lights.
Why Pineapples Tingle
Tingle into pineapple science.
How Ravens Solve Puzzles
Puzzle out raven smarts.
Why Wet Hair Looks Darker
Soak in wet hair physics.
How Slime Molds Think Without Brains
Navigate with the brainless slime mold.
Why Beans Make Gas
Toot into bean digestion.
How Horseshoe Crabs Helped Medicine
Thank the horseshoe crab.
December
Why Bread Gets Moldy
Grow into mold science.
How Penguins Stay Warm in Huddles
Huddle up with penguin warmth.
Why Hot Chocolate Tastes Better in Red Cups
Sip into color psychology.
How Trapeze Artists Catch Each Other
Swing into trapeze science.
Why Some Beaches Have Pink Sand
Beach into pink sand origins.
How Platypuses Sense Electricity
Electrify into platypus sensing.
Why Old Photographs Smell
Sniff through photo chemistry.
How Lie Detectors Try to Work
Detect the truth about lie detectors.
Why Fevers Help Fight Illness
Heat up to fever science.
How Fireworks Get Their Colors
Explode into firework chemistry.
Why Wet Stones Look Prettier
Polish up wet stone science.
How Archer Fish Hunt
Aim into archer fish hunting.
Why Cheese Has Holes
Hole up with cheese science.
How Snowflakes Are All Different
Crystal into snowflake science.
Why Calendars Have 12 Months
Month by month through calendar history.
How Geysers Erupt
Erupt into geyser science.
Why We Count to Ten
Count on fingers and toes.
How Dolphins Sleep
Drift into dolphin sleep science.
Why Yawning Is Contagious
Catch the contagious yawn.
How Diamonds Form
Pressurize into diamond formation.
Why Crabs Walk Sideways
Scuttle into crab locomotion.
How Holograms Work
Project into hologram science.
Why Bruises Change Color
Rainbow through bruise healing.
How Bees Make Hexagons
Hexagon into bee geometry.
Why Our Ears Pop on Planes
Pop into ear pressure science.
How Northern Lights Form
Light up with aurora science.
Why We Need Sleep
Dream into sleep science.
How Seed Banks Protect Plants
Bank on seed preservation.
Why Stars Twinkle
Today we learned that letting go is not weakness but wisdom.
Why 365 Days of Wonder
On this final day, we discovered that beginnings are constant.