The BEST Episodes of Bill Nye: The Science Guy

Every episode ever - ranked by fan votes!

Last Updated: Dec 7, 2021

Network: PBS

Comedian/scientist Bill Nye stars as the host of this show designed to get kids interested in the science of everyday, and some not-so-everyday, things. On a full range of subjects, including ecology, biology, chemistry and physics, Nye gives an easy-to-understand, yet informative lesson that both kids and their parents can enjoy.

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Chemical Reactions

#1 - Chemical Reactions

Season 2 - Episode 4 - Aired Mar 11, 1994

Bill is practically exploding with excitement about the "Chemical Reactions" show. Every single thing around you is made of chemicals. Plants, rocks, computers, food, and you are bunches of chemicals. All chemicals are built with elements, the 109 different symbols on the Periodic Table. Different combinations of elements make different chemicals. Lots of times, chemicals just sit around, but sometimes, when certain chemicals get together, they react. Chemical reactions take the starting chemicals and end up with new chemicals. Sometimes chemical reactions are hard to miss. Explosions, burning, color changes, and gas are all good signs that a reaction is going on. Some chemical reactions are less obvious - changes in temperature, a different smell, or differences in taste are clues that a chemical reaction is happening. The key is to figure out if you could get back the same chemicals you put in. If the answer is no, you've got a chemical reaction on your hands. Jus

star 9.17
6 votes
Light Optics

#2 - Light Optics

Season 2 - Episode 7 - Aired Sep 10, 1994

Don't stay in the dark - Bill Nye will help you absorb the science of light optics. Light is energy that normally moves in a straight line, but often something gets in the way. When light runs into something, three things can happen - the light can bounce off, it can go through, or it can be absorbed. Often all three things happen at the same time. Light bounces off mirrors. You see yourself in a mirror when light bounces off your face, into the mirror, and then into your eyes. Light goes through glass. If the glass is bent or curved, the light gets bent on its way out of the glass. The glass in a magnifying glass or a pair of eyeglasses is curved so that it bends light, making things look bigger. More light is absorbed by dark-colored things than by light-colored things. Colors are made when some light is absorbed while other light is bounced back. Black things look black because when light hits them, they absorb almost all of the light. In outer space, there are obj

star 9.14
7 votes
The Moon

#3 - The Moon

Season 1 - Episode 11 - Aired Nov 19, 1993

Let the moon master Bill Nye teach you the ancient and not-so-ancient secrets of the Moon. Wax on, wax off. The Moon grows bigger (waxes) and smaller (wanes) every 30 days or so. The word "month" comes from the word "moon". The Moon is the closest thing in space to Earth, and it's one of the most well-studied orbs in our solar system. We know that Moon rocks are rich in calcium and aluminum, that the Moon has no atmosphere, and that there are over a million craters on the Moon's surface. The Moon doesn't glow on its own, it reflects sunlight. Watch the Moon every night for a month as it grows, shrinks, and at one point disappears. The Moon doesn't actually change it's shape. It's the way the sun shines on the part of the Moon we see that makes the phases change. The Earth moves around the Sun, the Moon moves around the Earth. As the Moon moves through its orbit, the Sun shines on bigger or smaller portions of it. If you were looking at the Moon from the Sun, it woul

star 9.00
11 votes

#4 - Eyeball

Season 1 - Episode 20 - Aired Feb 11, 1994

Look no further ... Bill Nye is on the ball - the eyeball. For their small size, your eyes do an important job. By working with your brain, your eyes can tell the difference between thousands of different colors. They can follow a fast-moving hockey puck across the ice. They are even sending messages to your brain about what you're reading right now. Eyes work a lot like a camera. They take in light, focus light, and make images. With help from the brain, your eyes help understand the world around you. Light bouncing into your eye passes through an opening called the pupil. If you look in the mirror, your pupil is the black area in the middle of your eye. The pupil can open or close, depending on the brightness of the light. After passing the pupil, the light is focused onto the back of your eye by the lens, a thin layer of cells. On the back of your eye are special cells called rods and cones that are sensitive to light. These cells send electrical messages to your

star 9.00
7 votes
Rivers & Streams

#5 - Rivers & Streams

Season 4 - Episode 1 - Aired Nov 3, 1995

Water is massive; rivers are powerful. As rivers flow downhill, they wear away rock and soil to form canyons or winding curves in the land, called meanders. Sometimes rivers fill and overflow their banks. Rivers with too much water create floods that can carry away plants, trees, buildings and boulders. Rivers and streams support most of the ecosystems on land.

star 9.00
3 votes
Marine Mammals

#6 - Marine Mammals

Season 4 - Episode 3 - Aired Nov 17, 1995

Whales, dolphins, otters, walruses, and orcas are just like us, they’re mammals. Well, they’re not just like us. They live in the ocean. They breathe air, have hair, nurse their babies, and they are warm-blooded. They keep the same body temperature all day. To do that in the ocean isn’t easy. Water soaks up heat, so the ocean is really pretty cold. Marine mammals have all sorts of ways to keep warm. Whales, dolphins, and walruses have thick layers of fat called “blubber.” It’s great insulation. It holds their body heat keeping them warm in the cold ocean. Sea otters have thick layers of fur that cover their whole bodies. Otters fluff their fur to trap air between the hairs. It helps them float, it the air keeps them warm even when they dive deep hunting for food. These adaptations make it possible for marine mammals to live all over the world’s oceans.

star 9.00
3 votes

#7 - Earthquakes

Season 4 - Episode 4 - Aired Nov 24, 1995

Earthquakes happen when pieces of land in the Earth’s crust scrape together. The crust of the Earth is made of big slabs of land called plates that are constantly moving just a little bit. The plates scrape by one another, and sometimes they don’t move smoothly. An earthquake happens when the plates get unstuck suddenly and jerkily slip past each other. The majority of earthquakes occur along plate boundaries such as the boundary between the Pacific Plate and the North American plate. One of the most active plate boundaries for earthquakes is the massive Pacific Plate commonly referred to as the Pacific Ring of Fire. The fire comes from the volcanoes that form near the edge of the plates.

star 9.00
4 votes

#8 - Amphibians

Season 4 - Episode 13 - Aired Jan 30, 1996

Frogs, toads, salamanders, newts, and caecilians (worm-like animals that have backbones) are all amphibians, animals that spend part of their lives in water and part on land. Amphibians are slimy. Amphibians are cold-blooded that means their body temperature changes with the temperature outside. And as amphibians grow up, they go through metamorphosis.

star 9.00
3 votes

#9 - Volcanoes

Season 4 - Episode 14 - Aired Jan 31, 1996

Volcanoes are mountains made from molten rock. The Earth’s crust is divided into big slabs, called plates, which are slowly moving all the time. The plates are floating on the Earth’s mantle, a layer of gooey hot rock that flows like maple syrup. Some places in the mantle, the rock gets very hot and nearly liquid. It’s called magma. Sometimes the magma reaches the Earth’s surface and forms a volcano.

star 9.00
2 votes

#10 - Invertebrates

Season 4 - Episode 15 - Aired Feb 7, 1996

Worms, squid, clams, and flies are spineless creatures. They’re not afraid, they’re invertebrates – animals that don’t have backbones. Invertebrates are everywhere. You can find invertebrates in the sea, in freshwater, and on land. There are about 30 times more invertebrates than vertebrates on Earth.

star 9.00
3 votes

#11 - Heart

Season 4 - Episode 16 - Aired Feb 14, 1996

Your heart pumps your blood around your body, all hours, every day of the week, to keep you alive. Your heart is about the size of your fist, and it’s made of special muscle called “cardiac” (KAR-dee-ak) muscle. Cardiac muscle lets your heart keep the beat, it can also speed up or slow down, depending on what your body needs. Your heart works like an automatic pump – it squeezes, or contracts, and un-squeezes, or relaxes, to push blood through the four different sections of your heart. Valves, special one-way openings, are like little doors between the sections – making sure your blood moves in only one direction through your heart, to your lungs, back to your heart, and then around your body again.

star 9.00
3 votes

#12 - Caves

Season 5 - Episode 12 - Aired Apr 25, 1998

Caves come in all different shapes and sizes depending on how they were formed. Spelunkers (people who explore caves) have plenty of descriptive names for caves and the natural rocky features that form within them – soda straws, fried eggs, popcorn and draperies are just a few. Caves can be as simple as one straight passage with a few stalactites overhead, or as complex as a labyrinth, with many stalagmite-carpeted rooms.

star 9.00
4 votes

#13 - Erosion

Season 5 - Episode 14 - Aired May 9, 1998

Dirt, sand, and rock from the Earth’s surface gets blown, sliced, torn, swallowed and distributed all over the world. What was yesterday’s hill is tomorrow’s flat plain. The planet looks a lot different than it did when it formed four and a half billion years ago. The force of erosion, the slow wearing away of the land, has never ceased.

star 9.00
4 votes
Light & Color

#14 - Light & Color

Season 1 - Episode 16 - Aired Dec 24, 1993

Lighten up. It's the "Light and Color" episode. Without light, we wouldn't be able to see. It would be like living in a room with no windows, doors, or lamps. There's an old saying, "We don't see things; we see light bouncing off of things." We see things, and colors, when light bounces off things and into our eyes. White light, like the light from the Sun, is made up of all the different colors of light blended together. When white light hits something white, almost all of the light bounces into our eyes, and we see the color white. Things are different colors because some light bounces off and other light gets absorbed. An orange is orange because it absorbs all different colors of light except orange light. Grass is green because it absorbs all different colors of light except green light. Bill Nye's lab coat is blue because it absorbs all different colors of light except blue light. All colors, including black, are made in the same way. It's just a matter of ref

star 8.92
12 votes
Food Web

#15 - Food Web

Season 2 - Episode 6 - Aired Mar 25, 1994

Feeling a little hungry? Then grab a snack and watch Bill Nye the Science Guy's episode on the Food Web. When it comes to eating, all living things depend on other living things. Take a chicken sandwich, for example. The bread came from plants. So did the lettuce and tomatoes. The cheese was made from milk, which came from a cow. To make milk, the cow had to stay alive by eating grass. The meat came from a chicken who once ate seed, and maybe the occasional bug. The animals that helped to make your sandwich depended on other living things to survive. The lettuce, grain (for the bread), and tomato got by fine on their own. Then some animal came along (you). Plants are the only big living things that don't need other living things to survive. All they need are sunlight, carbon dioxide, and water to make their own food. But it doesn't stop them from being eaten -- no way. In fact, plants are great things to eat. All animals need them in some way for food – by the way,

star 8.91
11 votes

#16 - Brain

Season 2 - Episode 14 - Aired Oct 29, 1994

Bill Nye looks at how the brain controls the body and stores information

star 8.89
9 votes

#17 - Fluids

Season 5 - Episode 13 - Aired May 2, 1998

Fluids are cool; they ooze and swoosh. Whatever container you put a fluid in, that fluid will take the same shape. Milk poured into a pitcher forms to the shape of the pitcher. If you pour it into a glass, it takes the shape of the glass. You just can’t do that with a boulder. But with the right container, you could pour liquid rock from below the Earth’s crust. Fluids still act like fluids, even halfway to the center of the Earth.

star 8.85
33 votes
Earth's Seasons

#18 - Earth's Seasons

Season 1 - Episode 15 - Aired Dec 17, 1993

It doesn't matter if it's spring, summer, winter, or fall - Bill Nye is always in season. Every year, we experience the seasons. Some months have snow and rain, while other months have warmth and sunshine. Temperatures go from cold, to woarm, to cold again – winter, spring, summer, and fall. The cycle of the seasons takes one year, and the Earth takes one year to go around the sun. Coincidence? No way. The Earth's orbit around the Sun is flat, as though our planet were spinning over a tabletop. Compared with flat plane of its orbit, the Earth is tilted. Its axis, the imaginary line between the North and South Poles, is tipped over a bit. In June, the north half of the Earth (the Northern Hemisphere) is tilted toward the Sun, and it's summertime in places like Nye Labs in the United States. Meanwhile, the south half (the Southern Hemisphere) is tilted away from the Sun, and it's winter there, in places like Australia and South Africa. The Earth's orbit isn't quite

star 8.80
10 votes

#19 - Magnetism

Season 2 - Episode 1 - Aired Feb 18, 1994

They're on your refrigerator, they're inside your computer, and you're even standing on one right now. They're magnets, and forget about being repulsed. Bill Nye the Science Guy's "Magnetism" episode is totally attractive. All magnets have certain things in common. All magnets have two poles - north and south. You could take a magnet and break it into pieces and all of the pieces would have north and south poles. Ever play with two magnets? If you hold them with one magnet's north pole facing the other's south pole, they will stick together. If you put two of the same poles together, the magnets will push apart. With magnets, opposite poles attract, and "like" poles repel. Ever wonder why the Earth has a North and South Pole? The Earth's hot, churning, iron core is like a giant magnet. The magnetic force of the Earth stops a lot of harmful radiation from reaching us. Charged particles streaming from the Sun get pulled down by the Earth's magnetic field, creating the

star 8.80
10 votes
Ocean Exploration

#20 - Ocean Exploration

Season 5 - Episode 9 - Aired Dec 5, 1997

Ocean exploration is a tricky, risky business since humans can’t naturally survive under the ocean. Ocean explorers are constantly inventing new tools to help them dive deep into the sea. Over the last few hundred years or so, and especially in the last few decades, we humans have come up with all kinds of new ways to study the ocean. Even so, the ocean remains largely unexplored. It’s huge, cold, salty, and deep. Ocean exploration helps us understand our planet, and may help us solve the mystery of how life started on Earth.

star 8.78
9 votes
Pollution Solutions

#21 - Pollution Solutions

Season 4 - Episode 7 - Aired Jan 12, 1996

Dirty water, land, and air are a result of pollution. People are the only animals on Earth that make pollution. Garbage, burning fuel, chemicals, sewage, oil, and pesticides are all human-made things that make the Earth’s atmosphere, water, and soil unclean. Humans are even leaving trash in space, such as broken satellites, pieces of metal, paint from rocket skin, and even cameras and toothbrushes. Much of the junk people make and leave behind hurts plants, animals, you and me.

star 8.75
8 votes

#22 - Pressure

Season 3 - Episode 2 - Aired Jan 21, 1995

When you push something, you’re using pressure. Pressure depends on two things – the power of the push and the area that’s being pushed on. A push on a small area makes more pressure than the same size push on a big area. Pushing hard on something creates more pressure than a little nudge, naturally.

star 8.60
5 votes
Spinning Things

#23 - Spinning Things

Season 3 - Episode 14 - Aired Sep 15, 1995

A lot of things spin – bike wheels, footballs, hard disks in your computer, and even the Earth – they’re all twirling around. Spinning things have inertia, which means they keep spinning unless something slows them down. Bike tires keep spinning until you put on the brakes. A football spirals through the air until you catch it. The Earth keeps on spinning 24 hours a day, seven days a week. It’s been spinning for over four billion years.

star 8.60
5 votes
Blood & Circulation

#24 - Blood & Circulation

Season 2 - Episode 3 - Aired Mar 4, 1994

It's time for a heart-to-heart talk about blood and circulation with Bill Nye the Science Guy. Your blood is your bud. Without blood, your skin would dry up and fall off, your internal organs would die, and your brain would be kaput. Blood gives every cell in your body the food and oxygen it needs to survive. Blood also cleans up after our cells by carrying away waste. Blood even protects your body from disease. What more could you ask from a friend? Blood patrols your entire body. Blood is pushed around by a powerful pump called the heart. Every time your heart lub-dubs, blood is propelled through tubes called arteries, capillaries, and veins. Your heat pushes your blood in a complete loop around your body about 2,000 times every day. Your heart is a muscle, and, like all muscles, it can get stronger. A healthy heart needs exercise to stay strong. An average heart pumps about 70 times a minute, but a healthy, well-exercised heart pumps 50 or 60 times a minute. Heal

star 8.57
7 votes

#25 - Garbage

Season 1 - Episode 13 - Aired Dec 3, 1993

Garbage is a look at two different kinds of garbage -- biodegradable and non-biodegradable. Nye emphasizes the importance of recycling and cutting down on the amount of the waste that cannot break down. The music video "Recycle" has a familiar melody, taken from "Respect," the Aretha Franklin hit.

star 8.50
10 votes