# Bag of Wonder: The Train > A long freight train rumbles by: look inside the cars, cross a big bridge, count the cars. Food travels too! Then pull it apart. A free interactive 3D exhibit for children aged 2 to 6, from Curiosity's Child in Troy, Michigan. - Interactive exhibit: https://bagofwonder.com/look-inside/train/ - Ages: 2 to 6. The story is pitched at the youngest; the tap cards give older children more to chew on. - Cost: free, with no sign-in, no ads and no tracking. - Works on: phones, tablets and computers, in a web browser. Sound on for the narration. ## What it is A painted freight train for young children, with Sal the engineer: the engine, cars full of oranges and corn, a big bridge, the rail yard, and counting the cars. Wave to Sal and he waves back. Then pull the train apart, tap any part, and read a Did you know? card for the grown-ups. Free and narrated, for ages 2 to 6. How to play: press play to hear the story (read aloud in Kelly's voice, with the words on screen). Slide the time slider back and forth to see any part again. Slide "Pull apart" to see what is hidden inside. Tap any glowing button for a fact. ## The story 1. Good morning, poppets! Here comes a long freight train, rumbling along the tracks. Honk, honk! 2. At the very front is the engine. It's called a locomotive, and it pulls all the cars behind it. Up in the cab is Sal. Sal loves driving trains, and he loves waving to the children who stop to watch. Now you try, poppets: wave to Sal! 3. Now look inside the cars! Here are oranges from a warm place, corn from Farmer June's farm, little cars, and even milk. 4. This is a cold car, called a refrigerated car. It keeps the fruit cool and fresh, all the way. 5. Over the big bridge we go, high above the river. Rumble, rumble, rumble. 6. At the rail yard, the goods go from the train onto trucks, and the trucks take them to the shops. 7. The banana in your lunch might have traveled on a boat, and on a train, too! 8. Let's count the cars, poppets. How many can you count? Hold up a finger for each one! One, two, three, four, five, six, seven! 9. Look, poppets: a train on one table! The engine, a boxcar, a cold car with fruit inside, a tank car, and a piece of track. ## The parts, and what we tell children These are the tap cards, word for word. - **Locomotive**: The locomotive is the engine at the front. It is very strong, and it pulls all the cars behind it. - **Cab**: The engineer sits up in the cab, with big windows to see the track ahead. The engineer drives the train. - **Engine hood**: Under this long hood, a big diesel engine and its generator do the hard work. The big fans on top keep it cool. - **Diesel engine**: A big diesel engine burns fuel and makes a generator spin. The generator makes electricity. - **Wheels**: The electricity turns motors, and the motors turn the big steel wheels. Steel wheels roll along steel rails. - **Fuel tank**: The fuel tank sits under the engine. It holds lots and lots of diesel fuel for a long trip. - **Boxcar**: A boxcar is like a big box on wheels, with a sliding door on the side. Crates and boxes of food ride safely inside. - **Cold car**: A refrigerated car has thick walls and a cooling machine, so it stays cold inside. Fruit stays fresh all the way. - **Tank car**: A tank car is a round tank on wheels. It carries liquids, like milk or juice. The tank is sealed, so nothing spills. - **Grain car**: Corn from a farm rides in a grain car. It is poured in at the top, and it pours out at the bottom. - **Flat car**: A flat car has no walls and no roof, just a big flat floor. Cars and big machines can ride on it. - **Rail and tie**: Two steel rails sit on strong ties. The ties keep the rails the right distance apart, and the train's wheels roll along them. - **Sal**: This is Sal, the engineer. He has driven freight trains through Detroit for a long, long time. He drives the train, blows the horn, and waves to the children who watch. - **Did you know?**: Trains came before bicycles! The first steam locomotive ran in 1804. The first bicycle, with no pedals, came in 1817, and pedals in the 1860s. Boats came first of all, then the wheel, then the train, the bicycle, the car, and last the airplane in 1903. ## Getting the science right What we checked, and the myths we steer around: - The locomotive is a US-style diesel-electric: a big diesel engine turns a generator, the generator makes electricity, and electric motors turn the wheels. The cards say it simply: "a big diesel engine burns fuel and makes a generator spin. The generator makes electricity", then "the electricity turns motors, and the motors turn the big steel wheels". The look-inside is a painted cutaway of the locomotive (the engine and its generator along the hood, the cab, the fuel tank slung underneath); a real locomotive engine is often a V12 or V16 and sits along the length of the hood, with the generator at one end. - Sal is a story character, the engineer, painted for this exhibit (Sal was Jackie's idea): a man who has driven freight trains through Detroit for a long time and waves to the children who stop to watch. The engineer drives the train (the cab card says so). The horn is two short honks in the story; real locomotive horns also use longer patterns at crossings. - Boxcars have sliding doors on the sides and carry boxed and bagged goods. The painting shows the door slid open on crates and boxes of food, a picture of what is inside. - The cold car is a refrigerated car ("reefer"): thick insulated walls and a cooling unit, so fruit and vegetables stay fresh on a long trip. The inside picture is a cutaway, with oranges and bananas in crates and frost in the air. Today much fresh produce also rides in refrigerated shipping containers on trains and trucks. - Corn, like wheat, usually rides in covered hopper cars (a roof with hatches on top, chutes underneath). The painting shows a covered hopper with "JUNE" lettered on its side (Farmer June, from the Farmer exhibit), cut away to show the heaped corn, with a little pouring from a chute; the card says only that corn is "poured in at the top, and it pours out at the bottom", which is true of a hopper. - Cars (automobiles) usually ride in tall enclosed autoracks. The painting uses a flat car carrying two small cars, which really can carry cars, trucks and machines, so they can be seen. - Tank cars carry liquids such as juice, milk, oil and chemicals; the card says "like milk or juice". Milk once traveled in tank cars on many railways; today most milk goes by road tanker, though some is still moved by rail. The milk inside the painted tank is a picture of what a tank can carry. - Bananas grow in warm places and are shipped green in cold ships, then moved by train or truck to ripening rooms and shops. The line says a banana "might have traveled on a boat, and on a train, too", which is true of many but not every banana. The harbour is a painting; the little train waits on the quay. - A freight train can be a mile or more long; the page shows eight units (a locomotive and seven cars) so that a child can count them. The counting line says "one, two, three, four, five, six, seven" as the numbers appear over the seven cars. - The bridge is a stone viaduct: a bridge of many arches. The countryside (one straight track seen side on), the rail yard (two tracks, a loading platform and a paved apron) and the viaduct with its river are backdrops painted with Grok Imagine; the locomotive, the cars, Sal, the truck and the harbour are painted with Grok Imagine from Kelly's prompts too. The train is a row of painted cut-outs slid across the backdrops by the page, with wheels that shine as they turn and puffs of smoke, not a clip of a whole train. - The "Did you know?" card: the first steam locomotive to pull a train on rails ran in 1804 (Richard Trevithick, in Wales); the first bicycle, a running machine with no pedals, was shown in 1817 (Karl von Drais), and pedals came in the 1860s; boats are far older than any of them (dugout canoes about 10,000 years old have been found); the wheel is about 5,500 years old (around 3500 BC); the first practical car was built in 1886 (Karl Benz); the first powered, controlled airplane flight was in 1903 (the Wright brothers). So the train really did come before the bicycle. - Gentle wording: the train is never in a hurry, nothing goes wrong, no crashes. The first story stages are for the youngest; the tap cards give older children more. ## How to use it with children Watch the whole story with the sound on. At "Count the cars", count along out loud and hold up a finger for each number as it pops up. Wave to Sal when Ms Daisy asks, and he waves back. Then pull the train apart: find the cab, the engine, the wheels and the fuel tank, and ask which car carries what. At the table, read the "Did you know?" card together: trains came before bicycles. Ask more than you tell, and let the child drive. Then step away from the screen: line up shoe boxes or blocks as a train and load each car with a different toy "food" (an orange, a scoop of corn, a carton of milk). Sort a snack into "grows on a farm" and "comes in a box". Next time you cross a railway, count the cars together. A few minutes together is plenty. The exhibit is a doorway to the real thing, not a replacement for it. ## Credits and licenses The real scans, maps and photographs belong to their makers, under the licenses below. The words, story and code are Curiosity's Child's. - The train, Sal, the harbour and the cars on the flat car: painted with Grok Imagine from Kelly's own prompts, and slid and layered together in code - Sal was Jackie's idea - The countryside and the stone viaduct with its river: backdrops painted with Grok Imagine (Kelly's own) - The display table is a real scan from [Poly Haven](https://polyhaven.com) (CC0) - Real sounds from Freesound ([CC0](https://creativecommons.org/publicdomain/zero/1.0/), thank you!): [a heavy train passing](https://freesound.org/s/631590/) (golovlev.sound), [a locomotive horn](https://freesound.org/s/662553/) (JotrainG), [a forest river](https://freesound.org/s/442478/) (BonnyOrbit), [a locomotive in the yard](https://freesound.org/s/585818/) (waysidefilms), [birds on a quiet morning](https://freesound.org/s/135074/) (mzui) - Music-box tune made for this page - Narrated by Kelly, in her own voice ## More on the Things That Go shelf - [The Electric Car](https://bagofwonder.com/look-inside/car/index.md): An electric family car’s whole day: buckle up, drive the lanes, swish through the rain. Then pull it apart! - [The Excavator](https://bagofwonder.com/look-inside/excavator/index.md): Dig, scoop and pour! Meet Patrick, fill the dump truck, then pull the excavator apart. - [The Gas Station](https://bagofwonder.com/look-inside/gas-station/index.md): Fill up the car, look inside the pump, and find the giant tanks under the ground. Click! Full! - [The Airplane](https://bagofwonder.com/look-inside/airplane/index.md): Pack a suitcase, buckle up, take off, glide above the clouds and land. Then pull the airplane apart! - [The Mayflower](https://bagofwonder.com/look-inside/mayflower/index.md): Sail across the Atlantic in 1620: tall sails, a hundred people below deck, a storm, then Land ho! Blow like the wind, count nine weeks, and pull the ship apart. - [The Bicycle](https://bagofwonder.com/look-inside/bicycle/index.md): Ride along the street with Raphael and Leonardo, count the wheels, see the chain and brakes glow, then pull a real bicycle apart. Ring the bell! ## About Bag of Wonder A free library of interactive 3D "look inside" science exhibits, made at Curiosity's Child, a licensed home daycare in Troy, Michigan. Secular and science-based; welcoming to all. - All exhibits and how we make them: https://bagofwonder.com/llms.txt - For grown-ups and AI assistants: https://bagofwonder.com/look-inside/about/ - To cite: "The Train", Bag of Wonder, Curiosity's Child (Troy, Michigan). https://bagofwonder.com/look-inside/train/