Teacher Activity Guide: Scholastic's The Magic School Bus Explores The Human Body
Updated: April 8, 2004
The award-winning Magic School BusŪ has been helping teachers and children to explore science the fun way: through a series of fantastic adventures filled with humor and wonder. Like the best-selling books and the animated television show, Scholastic's The Magic School Bus CD-ROM programs motivate children to ask questions, try things to take chances, go places ... experience the world from highly unusual locations like the inside of a human heart.
Scholastic's The Magic School Bus Explores the Human Body takes you and the children in your class on an interactive voyage through Arnold's body. Ms. Frizzle, ever helpful, cheers you on through your wild ride. Her pupils welcome you into the class. And the Magic School Bus is at your disposal for truly one-of-a-kind discovery tours.
The story begins in Ms. Frizzle's wacky classroom, the starting point for all of The Friz's adventurous field trips. This time, Arnold, who never really likes to go on field trips anyway, gets left behind. Or does he? The fun begins as children soon discover that Arnold is the field trip! He swallows the Magic School Bus along with his lunch. Children suddenly find themselves taking a bus ride deep into Arnold's body.
On This Page
Overview
Activities
The Science Adventures are meant to help you and your students use and explore the CD-ROM program itself. But they go well beyond that; they contain activities and discussion starters that will bring meaningful science exploration right into your classroom.
Think and Discuss
Each Science Adventure includes an intriguing science question and an intriguing science answer. Ask your students the question. Allow them to brainstorm possible answers. You might be surprised at the creative and original ideas you hear. Don't discuss the answers right away. Encourage students to explore and find the answers during the trip on the Magic School Bus.
Computer Buddies
Pairing up students at the computer will encourage them to discuss the captivating science they'll encounter on the screen. Plus, two people working together will uncover more of the program's hidden science lessons, especially if you pair a shy student with a more out-going one.
Hands-On Science
Each Science Adventure offers hands-on activities to do before, during, and after exploring Arnold's body. Students can work in cooperative learning groups or on their own.
Computer Basics
Clickables
Once the program is up and running, many objects on the screen are "clickables": point the cursor at something and click the mouse to see what happens. If nothing happens, it's not a clickable.
The Classroom
The program begins in the left side of Ms. Frizzle's classroom, which is filled with wacky science projects that students can assemble. To explore the other side of the classroom, where a skeleton that students can assemble is, click on the sneakers in the lower right corner.
The Field Trip
Clicking on the small bus on the desk in the right side of the classroom will start the field trip inside Arnold's body. DON'T click on the bus until you are ready to take the field trip.
Travel
To move between body parts, look through the front window of the bus. Turn the steering wheel right or left (by clicking on it) until a sign for a body part comes into view. For example, a sign will appear that says, "To the Stomach." Click on the sign. Each body part allows you to move to at least one other body part. All body parts allow you to move to the nervous system by clicking on the nervous system icon. Then, from the nervous system, you can visit any body part.
Music
To turn the music on or off, click on the radio on the right side of the dashboard.
The Big Picture
To access an outside view of Arnold, click on the big red button on the top of the bus.
Road Map
For a map of where the bus has been, click on the glove compartment; then click on the map.
Experiments
In each body part, students can conduct various experiments by clicking on the Experiment Monitor Knob on the left side of the dashboard. This same monitor also gives you a view of where the bus is inside Arnold's body.
The Bus
To get to the back of the bus, click on the rearview mirror. To return to the front, click on the steering wheel in the lower right hand corner.
They Speak
Click on characters to hear them speak (especially if the character's hand is raised).
Video Games
Clicking on Ralphie's video game sends students to a game related to the body part the bus is visiting.
Stopping
After you've explored all 12 body parts and the map is complete, go to a body part where you can naturally exit Arnold (there are three in this game and, hint, hint, one is the mouth!). From there, click on the bus' keyhole. Watch what escapes from the keyhole, click on it, and then click on the windshield. Out you go! You've escaped from Arnold's body.
The Upper Digestive System
"Total Breakdown" is one way to describe the goal of the digestive system. The parts in this body system, beginning with the mouth, take whole pieces of food and liquids and break them down smaller, and smaller, and smaller . . .
Science Concepts
| • | In the mouth, the teeth, tongue, and saliva work together to break down food into smaller bits. |
| • | The esophagus moves food from the mouth down to the stomach. |
| • | In the stomach, acids and enzymes further break down food. |
Background
The adventure begins where the process of digestion begins: in the mouth. Arnold's teeth are grinding and crushing food. The Magic School Bus parachutes down the esophagus and splashes into the stomach, where students soon discover that Arnold has eaten a hamburger, chocolate bar, and other tasty foods. They learn that the stomach can stretch from a hot-dog-sized organ to a big "balloon," among other facts.
Important Tips
| • | The mouth activity (click on the Experiment Monitor Knobs on the left side of the dashboard - while in the mouth - to start activity) asks students to match the four basic flavors (sweet, sour, bitter, salty) to parts of Arnold's tongue that can sense them. |
| • | In the nose, users can click on seven basic scents and watch Arnold's reaction as he smells them. |
| • | The esophagus activity challenges students to click on the parts of the mouth and esophagus in the right order to squeeze food down Arnold's throat. |
| • | In the stomach activity, students can add acid and enzymes to Arnold's food to make it break down faster. Too much acid gives Arnold heartburn. |
Activities
Intriguing Science Question: Why doesn't the stomach digest itself?
1. Light the Way
Ask children: Is there any light inside your digestive system?
Suppose students were to really take a field trip inside Arnold. Would they see light? If they say yes, ask them where the light might come from?
Though light may enter your mouth, which has an opening to the outside, your insides are totally dark. That's why the Magic School Bus has its own high-power lights.
2. Mouth Meltdown
Ask children: Which foods "melt in your mouth"? (Easily break down as soon as you bite them?)
Saliva has enzymes that specialize in breaking down starch (which is in crackers, for example). Sugars are easy to cut apart too. But saliva leaves other foods, such as meats (mostly protein) and vegetables (fiber) relatively untouched. To observe the difference, have students hold a series of food bits in their mouths for 10 seconds, chew, and then swallow. Include crackers, popcorn, bread, bits of apple, peanuts, chunks of carrot, raisins, pieces of chocolate, and others.
Which ones change the most while in the mouth? Crackers, popcorn, bread, and chocolate dissolve right away; the others are less affected.
3. Ralphie's Point of View
Ask children: What happens after food enters your mouth?
As students explore the digestive system, ask them to describe in their own words how . . .
(a) back teeth are like falling rocks (crush things to bits).
(b) front teeth are like knives (cut and tear things).
(c) the esophagus is like a tube of toothpaste (squeezing action makes contents move).
(d) the stomach is like a food processor (grinds food up into bits).
The Lower Digestive System
"Use it or lose it" would be a good slogan for the digestive system. In the intestines, the body separates the useful parts of food from the non-useful parts.
Science Concepts
| • | The small intestine absorbs nutrients from broken-down food into the blood. |
| • | The large intestine absorbs water from waste. |
| • | Your body gets rid of food waste when you go to the bathroom. |
Background
The stomach sends its mushy, liquidy contents to the small intestine. There, the class learns that the small intestine of an adult is about as long as a single-story house is high, among other facts. When students click on food particles, the particles seem to break down and "vanish." Not so! The bus shrinks down even further to reveal tiny finger-like projections called villi. These villi absorb the useful nutrients in the food.
The food waste moves to the large intestine. Students watch the large intestine absorb water and minerals, leaving behind solid waste. The solid waste leaves the body through the anus.
Important Tips
| • | In the small intestine activity (start the activity by clicking on the Experiment Monitor Knobs on the left side of the dashboard), students adjust the length of the organ and observe how this effects the rate of digestion. |
| • | The large intestine activity allows students to observe how bacteria break down hard-to-absorb foods, make vitamins, and give off gas. |
| • | To go outside the bus (while in the large or small intestine) and explore, click on the rear view mirror. Then click on the arrow in front of Ms. Frizzle. |
| • | Outside the bus, click on the tool box to view the insides of the body using various instruments (magnifying glass, X-ray) |
Activities
Intriguing Science Question: Does food disappear after you swallow it?
Answer: When you eat food, none of it "disappears." It just breaks down into smaller and smaller bits. Some bits are useful and stay in your body. Other bits are waste. Your body gets rid of them.
1. Gurgle, Gurgle, Squish
Ask children: What makes your belly rumble? Can you tell where the noises come from?
The digestive actions of you intestines can be very noisy! (It's the intestines, not the stomach, that let out those embarrassing gurgles for all to hear.) Have students put their ear next to a partner's belly and listen. Liquids being squeezed through the tube sound squishy. Gas bubbles make low, rumbling sounds. The bacteria in your intestines eat food, and then give off the gas (mainly methane) as a waste product.
2. A Long, Winding Tube
Ask children: How can a really, really long tube, such as the small intestine, fit inside such a small space?
After exploring Arnold's small intestine, have students measure and cut a piece of rope or clothesline 6 meters (roughly 20 feet) long. The rope strand is equal to the length of an adult intestine! To get a sense of how such an enormous organ can fit inside a small space, challenge children to carefully "pack" the rope inside a small tissue box.
Cut a rope about 17 meters long (about 50 feet). This rope represents the entire digestive system, from mouth to anus! The stomach bulges a bit and the large intestine is thicker than the small intestine, but basically the digestive system is just one long and winding tube.
3. Cornu-scopia
Ask children: How does food change when you break it down into smaller and smaller bits?
Collect and display various forms of corn: corn on the cob, loose kernels in wet form, loose kernels in dry form, creamed corn, corn meal, and corn bread or muffins. (The corn meal and bread contain corn that has been broken down.)
For each corn product, describe how the appearance changes. Note the color, shape, parts or ingredients, texture, solidity, etc.). Can students see any part of the original corn in the other products? (Look for yellow coloring and tiny bits of kernel in the corn meal and muffins.)
What other products can be broken down into small forms? (How about peanuts into peanut butter.)
The Circulatory System
An action-packed organ from an adventure point of view, Arnold's heart makes for an exciting stop on the human body tour.
Science Concepts
| • | The heart and blood vessels make up the circulatory system. |
| • | The heart pumps blood all over the body. |
| • | This blood carries oxygen and nutrients to body parts. |
Background
Students learn that the heart is a fist-sized muscle that pumps blood all over the body through blood vessels.
The circulatory system is like a city bus system. The "buses" (blood) carry oxygen and nutrients to even the remotest parts of the body. The blood even passes through a kidney "car wash" for cleaning! Then it returns to the "station" (the heart and lungs) to reload.
Important Tip
| • | The heart activity (click on the Experiment Monitor Knobs on the left side of the dashboard to start the activity) allows students to make Arnold speed up or slow down, which affects his heart rate and blood flow. |
Activities
Intriguing Science Question: If blood is red, how come my veins are bluish purple?
Answer: Oxygen makes blood turn red. Blood that is blue in color (blood returning to the heart) is poor in oxygen.
1. Pump You, Up!
Ask children: How is the heart like a pump?
The heart is a muscle and, like all muscles, it can only contract. It can't expand. Have children see for themselves:
(a) Squeeze an open squeeze bottle (an empty one, please!). It will go back to its original shape and not any bigger.
(b) Squeeze it again, only this time feel the air rushing out of the top. Close the top and squeeze again. What happens when heart valves get blocked? (The heart can't pump blood through them.)
(c) To see how hard the heart works, squeeze the bottle for one minute. Count the squeezes. A heart can beat 60 to 80 times per minute for decades.
2. Have a Heart
Ask children: What does the heart look like? What words would students use to describe its color? Its shape?
After exploring Arnold's heart, ask children to draw a picture of a heart, as best they can. Children's drawings may be very "sketchy" and simple. That's okay. Have them compare their drawings with a picture or diagram of a real heart and discuss the differences. The main idea is that the heart isn't the shape of a valentine; it has chambers and tubes for blood to go in and out.
On the other hand, ask students to think of the heart as more than just a mechanical device. Throughout the ages, the heart has been used as a metaphor for love and other emotions and feelings. Ask students to write about what "heart" means to them.
3. 60-Second Weakling
Ask children: When can you feel your heart speed up? How do you feel when your heart rate changes?
In Arnold's heart, students can click on the Experiment Control Knobs on the dashboard to explore how heart rate affects muscles and other body parts. Speed up Arnold's heart rate, and he starts running.
Have students stand with their arms straight out for 60 seconds. What happens when muscles use up more oxygen than they receive? How do their muscles feel? (Tired and weak; after several minutes, they ache.) How long can muscles keep working?
The Respiratory System
Ask your students what happens when bluish blood cells take on oxygen. Answer: They become reddish.
Science Concepts
| • | When you breathe in, the lungs take in air. Air contains nitrogen, oxygen, and a few other gases. |
| • | The lungs add oxygen to blood. |
| • | Carbon dioxide leaves the lungs. |
Background
Red, white, and blue are the basic colors of Arnold's lung. Blue blood cells and vessels, low in oxygen, enter the lung. Red blood cells and vessels, newly rich with oxygen, head from the lung to the heart. Oxygen is transferred from the lung to the blood via puffy air sacs called alveoli.
Air is a mix of nitrogen, oxygen, and a few other trace gases. After it passes through the lungs, carbon dioxide and other leftover gases exit.
Important Tips
| • | In the lung activity (click on the Experiment Control Knobs on the left side of the dashboard to start this activity), students can change the amount of oxygen, nitrogen, and carbon dioxide Arnold breathes. The wrong mix makes Arnold cough or turn blue. |
| • | Point out to students that the valves they see in the lungs go to and from the heart; the valves in the heart go to and from the lungs. |
Activities
Intriguing Science Question: How come food doesn't go down into my lungs when I eat?
Answer: When I eat, a valve closes off my windpipe so food won't go into my lungs. When I breathe, a valve closes off my esophagus so air won't go into my stomach.
1. Squeeze Play
Ask children: How do the lungs force air out and take it in?
To show this, have students put a hand on their chest as they take a deep breath. The heart only contracts. Does the lung only contract? Or does it expand, too? (It does both.) What forces the lung to expand? (Rib muscles.) Tell students to breath again, only this time place a hand just below the lungs on their diaphragm. How does the diaphragm change during a breath? (Breath in, and it gets smaller; breath out, and it gets bigger.)
2. Breathing Easy
Ask children: When does your breathing rate speed up?
Students can change Arnold's breathing rate by making him run or by changing the mix of gases in his lungs. Ask children to think about when their own breathing speeds up. (When they exercise, get angry or excited, wake up, or otherwise become more active). When does it slow down? (When they're sleeping, resting, or otherwise inactive.) Why do they breath harder when they're active? (The body systems, such as muscles, speed up their activity, so they need more oxygen.)
To find their breathing rate, have students sit very still for at least 10 seconds. Tell them to count the number of times they breathe in and out (that's one breath) from START to STOP. Using a stop watch, start timing and then stop after 30 seconds. For better accuracy, repeat this step twice. Use the middle breathing rates for each student and graph them on a class bar graph.
3. Where's the Air?
Ask children: Is air a thing?
A common misconception is that the air we breath is "nothing." This mixture of invisible gases has mass and takes up space. Can students prove it? An easy way is to breath in. The lungs expand because they are full of air. If air were "nothing" it couldn't make our lungs enlarge. Another demonstration: weigh a deflated basketball on a balance scale. Now inflate it, and weigh it again. The inflated one weighs more!
The Liver
The liver is a hard-working organ that makes and processes important chemicals.
Science Concepts
| • | The liver is your body's chemical factory. |
| • | The liver also stores fat. |
Background
The liver is just to the right of the stomach, under the rib cage. It cuts apart and combines chemicals to render dangerous ones (such as alcohol) harmless or other ones useful.
Important Tip
| • | In the liver, children can click on an icon like the Experiment Monitor Knobs to see how the liver processes proteins, fats, old blood cells, and more. |
Activities
Ask children: What happens to fatty foods inside your body?
The liver helps your body break down or change carbohydrates, fats, and proteins so that your body can use them.
To show how it works, smear two dishes with lard, margarine, a greasy french fry, or some other oily substance. Put one dish in a tub of water for a few seconds. Have students run a finger across the dish. It still feels greasy!
Add a squirt or two of dish detergent to the tub. Explain that this detergent works much the same way as bile, an oily chemical made in the liver. Swish the water to disperse the detergent and place the second dish in the tub. Lift it out and feel the surface. Is it slimy? The detergent has surrounded the bits of grease, forcing them to separate from the dish.The bits of grease are still there; each one is just hidden inside a film of detergent like a nut inside a shell.
Bile "washes" and "packages" fat in much the same way. The liver stores these little fat packages until fat-digesting chemicals "eat" them.
The Kidneys
To circulate means to go in circles. That's what your blood does all through the body. One pit stop is the kidney, which scrubs the blood of poisons and waste so the body can use it all over again.
Science Concepts
| • | The kidneys clean the blood. |
Background
Like the heart, the kidneys are about the size of a fist. Each kidney filters blood to remove waste and poisons.(A common misconception is that they're connected to the digestive system and collect liquids that you drink; they're not, and they don't.)The leftover liquid leaves the body as urine
Humans have two kidneys, but can live with one if they give a kidney to someone who needs one.
Important Tips
| • | Children can alter the water and salts in Arnold's diet to see how the kidneys still manage to keep a steady amount of each in the blood. (To start this experiment, click on the Experiment Monitor Knobs.) |
| • | From the kidneys, the bus can travel to the heart (via blood vessels), but not to the digestive system. Point out that this is because kidneys are part of the circulatory system, not the digestive system. |
Activities
Ask children: What do filters do?
Show how filters clean liquids but don't always get out everything. Put three coffee filters in coffee baskets and put them over a sink or pan. Ask students to test if the three filters will clean ...
(a) mud out of muddy water (most of it).
(b) salt out of salty water (no, though some salt may be visible on the filter after it dries out).
(c) the coloring out of colored water (no, though the filter will absorb some of the coloring).
To show how it works, smear two dishes with lard, margarine, a greasy french fry, or some other oily substance. Put one dish in a tub of water for a few seconds. Have students run a finger across the dish. It still feels greasy!
Ask children: What's it like to receive or give a kidney?
After learning how Arnold's kidney works, explain that sometimes people need to replace one of their kidneys. Have students research organ donor programs locally. Check with a hospital or look under "Organs and tissue" in the yellow pages. A hospital may be able to put you in touch with a kidney recipient or donor who is willing to talk to your class.
The Skin
Every day of our lives, we all wear a suit - a suit of skin. Skin is the only body organ that separates our delicate innards from the world outside.
Science Concepts
| • | The skin is one big organ that protects the insides of your body. |
| • | Skin allows some things (sweat, for example) to pass through, but blocks other things (dirt, for example) from getting in. |
| • | Sweating helps keep the body cool. |
Background
Students may be surprised when they discover that Arnold's skin is more than just skin. Lurking inside are nerves, blood vessels, sweat glands, oil glands, hair follicles, and other miniature body parts. Many of these tiny parts produce substances that protect your body: oil keeps you from drying out, sweat cools you off (when it evaporates), tears cleanse your eyes, and earwax protects your ears from dust, dirt, and bacteria.
Important Tip
| • | Click on the Experiment Monitor Knobs on the dashboard of the bus to adjust Arnold's temperature. The hotter he gets, the more blood flows to the skin's surface and the more he sweats. |
Activities
Intriguing Science Question: Why does my face turn red when I exercise?
Answer: When your body heats up, hot blood is sent to the skin, which turns red. Heat escapes through the skin and you cool off.
1. Skin Deep
Ask children: Does your skin look the same all over?
After viewing Arnold's skin from the inside, students can closely observe their own skin from the outside. A magnifying glass or hand lens is helpful. Have students explore the skin on their arms and record all the features they see. You may want to prepare a reproducible with a list of skin features to find:
Hair
It's everywhere, even in bare-looking spots such as the inside of the elbow. In these areas, the hair may be microscopic.
Wrinkle
The knuckles are extra-wrinkled because the skin over them stretches and contracts a lot.
Freckle
"Tan" spot that darkens in the sun due to active pigment cells.
Wart
Wart viruses cause skin cells to grow abnormally.
Scab
Blood that has dried. Scabs heal from the edges inward, as new healthy cells grow to replace them.
Bruise
Clotted blood beneath the skin
Callous
Hard, tough skin formed by constant irritation or pain to an area.
2. No Sweat
Ask children: Why does sweating keep you cool?
Have students wave a hand back and forth in the air. Does it feel cooler, warmer, or about the same. (A little cooler or about the same.) Dip the back of the hand in water and wave it again. Cooler or warmer? (Cooler.) If available, coat the back of the hand with rubbing alcohol and wave a third time. The hand will feel cooler still.
As liquids evaporate, they carry away heat from your body. You feel cooler. The faster the evaporation, the more "cooling effect" you feel. Alcohol evaporates faster than water, and so cools you better.
3. Bathtub Science
Ask children: Why does your skin wrinkle in the bathtub?
In the tub skin actually fills up with water. To demonstrate, slice a large peeled potato in half and cut off each end to make a flat base. Scoop out the center of each half. Set the two halves in a pan that contains about an inch of water. Put a spoonful of water inside one potato, and a spoonful of salt water in the other. Wait overnight.
Then check the water levels; the potato with the saltwater will be fuller. This is because less salty water (in the pan) moves toward more salty water (in the potato). The water seeps through the walls of the potato, just as water can seep through skin.The fluid inside your skin is salty. So the non-salty bathtub water seeps through your skin to the salty fluid inside you.
The Nervous System
Does your right hand know what your left hand is doing? For the big picture, you need a lot of little nerves - and a brain to take charge of them. Arnold's brain is the command center that controls all his bodily functions.
Science Concepts
| • | The nervous system includes the brain and a network of nerves. |
| • | The brain sends and receives messages along the nerve network in order to control all of the body's functions.. |
Background
If the heart and blood vessels are like a bus system, carrying cargo all around the body, the brain and nerves are like a telephone system. The brain is the "operator" in control of sending and receiving messages and the nerves are the "wires" for transmitting the messages. The brain itself is a massive bundle of nerves.
The nerves are the key link between all the body's systems. They're EVERYwhere. That's why you can always travel around Arnold's body in the nervous system.
Important Tips
| • | In the brain, children can click on the parts of Arnold's brain to see which functions they control (language, muscle movements, and so on). |
| • | From the nervous system, students can access any of Arnold's body parts. Point out that this is because nerves exist in every single part of your body. |
Activities
Intriguing Science Question: Why does my foot fall asleep?
Answer: When you sit on your leg, you squeeze a big nerve (and an artery) in your leg, which blocks messages to the brain. When you stand up, the "tingly" feeling is caused by the reflowing of blood and messages reaching the brain.
1. Fun With Nerves
Ask children: Why does your "funny bone" feel funny?
To a surgeon, nerves are pearly white strands. They're usually deep inside the body and branch into a complex web of microscopic nerves near the surface.
Students can feel one nerve that's thick and close to the surface: the one that triggers their funny bone. Bend either arm just a little bit. Feel the back of the elbow for a groove. It's a distinct canal between bones. Your "funny bone" nerve runs along this groove. Press it, and it feels "funny." This is actually a pain sensation.
2. The Little Letter Game
Another simple nerve game is for one student to use one finger to trace a big letter on another student's back. Can the other student guess what it is? If so, the tracer makes another letter, this time a little smaller, and so on, until the tracee can't name it. Have partner switch roles and repeat the activity.
Then discuss the science: The nerves on the back are fewer and farther between than the nerves on the lips, fingers, and other sensitive areas. They just aren't as good at picking up fine sensations. To compare, repeat the activity, with eyes closed, on the palm of the hand using a ball point pen that's clicked "off."
3. Brain Overload
Ask children: How does the brain process all the messages it receives?
The brain is only able to process a certain amount of information at one time. If too much comes in at once, it can get jumbled.
To observe how, have the children tap a finger on their desk. Simple, right? Next, tell them to squeeze the fist of their other hand over and over - while they are still tapping. While they are tapping and squeezing, have them add a third task - shaking their head back and forth. For those who can do all three, add a fourth - tapping a foot. It will be difficult for most students to do all four tasks at the same time, because the brain goes into overload.
