847 Compass needles
Magnetic Domains. There are 847 compass needles attached to a disc. Because they are so close together, they influence each other. With a magnet, the compass…
A riddle for intelligent and patient people
Puzzles for the sharp-minded and patient. Trickier than it seems: these eleven puzzles with strings, boards, and rings are challenging. One of them cannot be…
A Table with loose Legs
Three, two, one – stable. How many supports do we need to stabilize a tabletop? Without screws, without glue, of course. Sharp-minded (and experimental)…
All Triangels are the same
Central projection: Using various triangular shapes to cast congruent shadows onto a patterned wall with equilateral triangles.
Angled Mirrors
Many polygons. Two mirrors positioned around an axis at various angles: a simple way to create shapes with many sides (polygons). At certain angles,…
Ball in a Bowl
Shorter path = faster to the goal? A question that occupied the best mathematicians three hundred years ago. This competition compares two parallel tracks,…
Ball sorting machine
Playful tidying up. Yellow. Red. Blue. This machine sorts the small, medium, and large balls among Pierre Andrès' “Machines Singulières” in a playful manner.…
Beam Bridge
The simplest form, but not the most stable. This bridge demonstrates the forces acting on a straight beam when it is loaded and supported only at its two…
Bouncing (Steel) Ball
Ping-ping, not ping-pong. When a ping-pong ball drops onto the table, its sound is unmistakable. A tapping noise that grows quicker and quicker. This happens…
Break the code
Qxpoa gvp pbuu: Cryptography. An encrypted text appears on the monitor. The challenge is to decrypt it with as few errors as possible. But there are over four…
Bridge the Gap
Building bridges is not so easy - especially when you are not allowed to use nails, screws or glue! Here you only have nine identical wooden blocks at your…
Catenary Arch
Building solid – like the Romans. An arch as a delicate structure: reconstructing what the Romans perfected. Understanding what gives their elegant arches…
Chance Happenings
Capturing randomness – with dice. Four faces of these dice are white. The other two faces show a red circle. After each roll, the dice with the red circle…
Changeable Weather
How do you determine the average value of numerous individual measurements? Here, the average monthly rainfall can be determined experimentally.
Christmas Balls
Round shapes, angular gaps. The spheres are indeed round, despite the triangular gaps between them. Can this really be? If a sphere is missing in the…
Conic Sections with Laser
Ellipse, parabola, hyperbolic branch, or hyperbolic arm: Cross-sections of a plane through a geometric body. In this case, a cone. A laser beam circling the…
Convection cells
«Convection Cells» Warm air rises, as does warm liquid. This forces air and moisture to descend in other areas. The structures that form resemble cauliflower…
Conway Cube
Test your spatial imagination. Assemble nine pieces to form a cube. Three 1x1x1 cubes and six 2x2x1 cuboids. It seems simple, what the renowned British…
Diced Snake
At some point, it’s probably going to work... All sixty dice lined up: what number shows the head of the snake? Now move forward by that number. Roll the…
Digital Sundial
"Digital" sundial. It casts no shadow. Instead, it displays the time using illuminated numbers—without any electronics. A combination of aesthetics and…
Disappearing Ghost
The ghost disappears. Where did it go? The ghost reappears. Where did it come from? A puzzle made of three parts: one base element, two pieces to swap. How…
Distorted Room (Ames Room)
Little one grows tall. An absolutely ordinary room, at least when viewed through the peephole. But wait, the little brother grows taller than the big sister…
Do they fit in the Box?
Too big. Or is it? The cube fits into the glass cube. Clear enough. But the pyramid, the star-shaped object? Too big. Some objects appear larger than they…
Drawing on the Move
Elegant circles, spirals, and ellipses. Above a disc with variable rotational speed lies a ruler. If the pen is held still along the ruler, circles are drawn.…
Efron’s Dice
Loaded dice. The numbers on the faces of these four dice are nothing like what we’re used to. And they really get your brain working. The first player picks…
Elliptical Mirror
This έλλειψις has only one goal. At one focus of this mirrored ellipse stands a rotating periscope. At the other focus, a colored cone. Looking at the…
Emotion detector
Measuring skin resistance. The skin resistance is influenced by the subject's emotions: the stronger the emotions, the lower the resistance. Here, the skin…
Encoding Text - Caesar’s disc
« Caesar’s Wheel » Encoding and decoding with two rows of letters that can be shifted relative to each other. Even in Caesar’s time, information was protected…
Equal Times
Meeting – in the middle. On this track, a tautochrone, the time it takes for a ball to reach the lowest point is always the same. If we release two balls,…
Find the Fish!
Fits, from head to fins. The fish, the wire frame next to the image, fits in only one spot into the pattern with the "water lilies." The pattern with many…
Generator track
A magnet generates electric current. A track with a magnetic toy railway on it runs through a large coil. When the toy track is moved in the coil, a current…
Gothic Arch and Flying Buttress
With pillars and arches. Like in a cathedral: this is how forces act in a structure with a tall pointed arch and a system of buttresses. What significant…
Gravitational model or Energy Well
The potential well. Orbiting the gravitational center: once launched, the ball takes wide rounds. For minutes, it gradually accelerates. Its circles become…
How big is a Million?
Incredibly large. 999,999 yellow balls in a glass cylinder – and one black one. Where is it? What is a million? Through the search, a concrete task turns an…
How many Smarties?
Estimate – and verify. The many colorful Smarties are tempting – and they spark curiosity. How many are there? Many, very many, maybe thousands. How many…
Hyperbolic Slot
Straight rod passes through a curved slot. Impossible, that’s the first thought. But the experiment proves otherwise. The straight rod moves without contact…
I am a function
Three steps forward, one step back. The point on the screen moves along. The curve displayed on the screen is the target. Goal: move closer, move away, and…
Ink Fractals
Fingers grow fingers. As the ink spreads between the two acrylic plates, beautiful fractal patterns form. Finger-like structures that resemble ink…
Jumping Water
Fascinating Water Arches. Is solid water flying through the air? Beautiful: sometimes, continuous arches form, almost like tent poles, but made of water.…
Kalliroscope©
Magic and Beauty of Flowing Motion A vortex generator or rather a spectator par excellence. It allows for enchanting, seemingly chaotic, yet somehow regular…
Lights ON
Seven lights, seven buttons. The goal: make all seven lights turn on – or none at all. Pressing a button affects three lights and causes a state change: from…
Liquid Dynamics
Chaotic eddies, turbulent swirls – and calm zones. Turbulences become visible. In the flow tank, they appear in the water. Very similar to what happens in a…
Loose Stone Bridge
Brilliantly strong and simple. Loose stones, assembled in the correct order, form a bridge capable of bearing weight. Even in a small format, it can support…
Lying Water Disk
Water shapes sculptures. When two water jets collide, the water is deflected sideways. A water membrane forms, creating a disc. The pressure in the two pipes…
Machine with Concrete / Machine set in Stone
The Eternity Machine. Twelve worm gear mechanisms for eternity! An impressive example of mathematics illustrated mechanically. With each successive gear, the…
Magic Wave
A mechanical work of art: A rhythmic rise and fall of metal segments, reminiscent of traveling waves. With a remarkable setup, the artist induces phenomenal…
Magic Wave Model
Magical wave in the stairwell – principle clearly explained. A rotating arm, cords, guide points, and straight metal segments create a wave-like motion that…
Mirror cubes
Create different figures with coloured wooden blocks and on a mirror surface. What does the built cube world look like mirrored several times?
Misty Messages
Two patterns, one image. From a distance, the surface on the plate looks like grey fog. But when we place a second plate exactly on top, an image is…
Möbius Cube Loop
Infinite puzzle. The Möbius strip, assembled from cubes. The building blocks are cubes and corner pieces. The faces of the cubes are painted on their…
Moebius Strip
Loop without end. Most things have two sides, but not everything. Among the exceptions is the Möbius strip. When we ride along it with a small train, we…
Moiré
It’s all a matter of perspective. Black point clouds: this impression is created by two perforated plates mounted one behind the other at a certain distance.…
Mozart’s Dice Music
Compose like Mozart. Roll the dice 16 times, select 16 bars, and voilà – a composition: as simple as that, according to Mozart. Following his idea, composing…
Non-round Wheels
And yet they roll! With the right rolling surface, even a square rolls perfectly round. This applies to a pentagon as well as to any other regular…
Pendulum Wave
Chaos in perfect alignment. Eleven pendulums of different lengths. Once released, they swing in disarray. And yet, every ten seconds, they return to perfect…
Penrose Parquet
Aperiodic pattern. In the aperiodic Penrose tiling, subpatterns repeat irregularly, even though shapes like hexagons or stars appear throughout. Using only…
Pi
The first 20,000 decimal places. π, the mysterious number – displayed as a digit spiral on a poster. π (Pi) is a natural constant that represents the ratio…
Population Growth
How fast – and where? Current population figures displayed on a world map, by continent and overall. For each continent, the counters show how many people…
Pythagoras’ Theorem - Easy to weigh up!
a² + b² = c² with stars and bunnies. The square of the hypotenuse and the squares of the legs can be weighed against each other, as they are made of identical…
Pythagoras’ Theorem - flows from this
a² + b² = c² The Pythagorean theorem describes a transformation of areas. In a right triangle, the sum of the squares of the two shorter sides equals the…
Quasi-Crystals
Golden rhombohedra. When correctly assembled, the various bodies (cubes stretched along their diagonals and cubes compressed along their diagonals) form a…
Quick thinking
The moment of shock in road traffic - not just a simple reaction but also thinking! Unlike the simple reaction time, this also involves thinking quickly:…
Rhombo Puzzle
Rhombo-dodecahedron from parallelepipeds. Twelve building blocks (each consisting of two connected parallelepipeds) can be assembled to form a…
Rocking Roller - the Oloid
Wobbles, but goes straight. The oloid has only one surface. It is the only known shape that fully unwinds as it rolls. This means that every point on its…
Sand images
Sliding, floating, flowing So beautiful, so fascinating: The sand, moving here between glass plates, tells a story far beyond that of an hourglass. When it…
Sculptures in stroboscopic light
« BLOOM Revelation » and « BLOOM Accordance ». Sculptures come alive: single images, shown in rapid succession, are combined by our brain into a seamless…
Shepherd’s Sundial
North? Not relevant. A simple sundial, like those used by shepherds for centuries. The advantage of this clock is that knowing the north direction is…
Soma Cube
7 pieces = 1 cube. Each of the seven components of this large cube is a polycube. This means each piece consists of several small cubes. Spatial imagination…
Square Puzzle and the Square to Triangle-Conversion
Disassemble and reassemble – discrete geometry. Square puzzle: Nine square tiles of different sizes. Arranged correctly, they fit into an almost-square…
Squaring the Circle
Everything always has two sides. From one side, it looks like a square; from the other, a circle. It’s all a matter of viewpoint and perspective. The…
T-Puzzle
Frustratingly simple. Four pieces make up a puzzle. When placed correctly, they form the letter T. Child’s play. But: is this task really that easy?
Template Code
Untangling the letter jumble. Perfectly possible, with the right template. Using it in reverse, you can encrypt a 36-letter message, almost impossible for…
Tetrahedron Puzzle I
Three-sided pyramid, puzzle with two pieces. Spatial imagination is required: when correctly combined, these two equally sized bodies form a…
Tetrahedron Puzzle II
Three-sided pyramid, puzzle with four pieces. Spatial imagination is required: when correctly combined, these four equally sized bodies form a…
Tetrahedron Puzzle III
This puzzle game is mainly about spatial imagination. Four (2 equal) bodies made of spheres are to be assembled to form a tetrahedron.
Th shortest Way is not always the quickest
Marble race. Three tracks with the same height difference and the same horizontal distance, but different curves: the straight path is the shortest,…
The big is in the small: crystals
Amazing Order Shake it, please. When the balls come to rest, they arrange themselves into regular patterns. These patterns can be compacted, almost to…
The Circle’s the Limit!
A circle with many corners. Reflect green laser light to form a triangle, a quadrilateral, a pentagon, a … The more corners this polygon has, the more it…
The finest difference
How fine is your dexterity? Very fine: experience how this is defined for you with this exhibit. You can feel when something sticks out by ten millimeters.…
The Tea Leaves Experiment / Tea Cup Experiment
«Everyday Physics» Experiment like Albert Einstein. In a paper about river meander formation, he wrote: «I begin with a small experiment that anyone can…
Thread Models
Straight threads, curved surfaces. Rotatable cylindrical model: a cylinder becomes a hyperboloid. A surface generated by the rotation of a hyperbola. Movable…
Towers of Hanoi
Rearranging – how many moves does it take? Five disks stacked on a pole, arranged from largest to smallest. These five disks need to be moved to one of the…
Watch Water Freeze / Ice Flowers
Watch Water Freeze Crystals form on the cold surface, like frost flowers on windows, a sight we see less often thanks to better insulation. Here, you can see…
Water Parabola
Parabola in a natural phenomenon. As the rotational speed of this container increases, the water surface inside curves. The faster it rotates, the steeper the…
Weird Wheels
Not round, but it rolls round. These discs aren’t round, but when they roll, their axis stays at the same height: solids of constant width. Disc-shaped bodies…
Wind Machine
Breeze, storm, hurricane. From a gentle breeze to a raging storm: play with the wind. Reduce your surface area or expose as much of it as possible to the…
Wobbly Bridge I Arch Bridge / Wobbly Bridge II Suspension Bridge
Suspension bridge – an arch bridge viewed from a different angle and subjected to a different load. Resembling a suspension bridge, the chain bridge reflects…
Wolf, Goat and Cabbage
Keep calm, ferryman! Task: transport cabbage, goat, and wolf to the other side of the river. Tricky, since only one other passenger fits on the ferry. The…
Your Birthday in Pi
Ten million decimal places. Somewhere in π lies your birthday or your license plate number. This computer station can find any six-digit combination. At…
Agar Cell Diffusion
Use cubes of agar to investigate how size impacts diffusion. All biological cells require the transport of materials across the plasma membrane into and out of…
Anti-Gravity Mirror
Learn how to fly with this neat mirror trick. A reflection of your right side can appear to be your left side. Try this activity and you'll appear to perform…
Life Size
Explore the size and scale of microscopic biology. Not only is it hard to conceptualize things that are too small to see, it’s often surprising to discover the…
Asseln unter der Lupe - inklusiv
Asseln sind bestimmt keine besonders beliebten Haustiere – umso mehr eignen sie sich aber als Einstieg in die Tierkunde. Was machen eigentlich Zoologen, deren…
CSI Technorama – forensics
Regardless of whether it is a burglary, an accident or a felony, crime scene investigations always begin with securing the evidence. Are there fingerprints?…
Happy hour on the ISS – water purification
Even astronauts on the International Space Station ISS enjoy drinking a Campari Soda from time to time – but where do they get the soda water from? There is no…
Lighting effects in nature and the home – fluorescence
How can you light up fluorescent objects? Where do lighting effects occur? You extract fluorescent dyes from everyday objects like pudding mixes or laundry…
Radiant insights – radioactivity
CERN in Geneva, the catastrophe in Fukushima, new radiotherapies for treating cancer – atomic and nuclear physics are constantly discovering new findings that…
The beauty in the beast – scientific methods
It is safe to say that isopoda (woodlice) are not the most popular pets – but they are all the more useful for zoology. What do zoologists actually do when…
Acoustics
Aggregate states
Algorithms
Animals, plants, habitats
Atomic and quantum physics
Atomic structure
Automats
Biology
Buoyancy
Chaos
Characteristics of life
Chemical Reactions
Chemistry
Colors
Computer science
Cryptology
Currents
Data and information
Design elements
Earth sciences
Electricity
Electricity and energy
Electricity and magnetism
Elektromagnetismus
