Science Shows Demonstrations

See also: Liquid Nitrogen, Dry Ice, Special Occasions

This category features demonstrations designed for large audiences, assemblies, or public events, where science is performed with dramatic effect. Because they rely on spectacle, presenters should always rehearse carefully before performing live.

Demonstration	Materials	Difficulty	Safety	Summary
Genie in a Bottle	★★☆	★★☆	★★★	When manganese dioxide is added to concentrated hydrogen peroxide, it rapidly decomposes into water and oxygen gas. The escaping oxygen propels a mist of water out of the container, creating the dramatic effect of a “genie” emerging from the bottle.
Geological Timeline with Toilet Paper	★☆☆	★☆☆	★☆☆	Using 46 sheets of toilet paper to represent Earth’s 4.6 billion-year history, students create a scale model timeline where each sheet equals 100 million years. Timeline markers show that most major biological and geological events occur only in the last few sheets.
Fire Tornado	★★★	★★☆	★★★	This dramatic demonstration shows how a spinning column of fire can be created using a rotating screen cylinder and a flame source. It models the dangerous fire tornadoes that occur in extreme wildfires when hot air updrafts combine with swirling winds.
Water to Wine to Milk to Beer	★★☆	★★☆	★★★	This dramatic chemistry demonstration makes a liquid appear to transform into water, wine, milk, and beer as it is poured from one glass to another. The sequence involves pH indicators, precipitate formation, and gas release, illustrating multiple chemical concepts in a visually striking way.
Water Into Wine	★★☆	★☆☆	★☆☆	This demonstration uses the pH indicator phenolphthalein and sodium carbonate to make water appear to turn into wine or blood. The liquid changes from colorless to pink or red under basic conditions, and can be reversed to clear again by adding acid or blowing carbon dioxide into the solution.
Blood Model in a Bottle	★☆☆	★☆☆	★☆☆	This activity creates a model of blood inside a bottle using food coloring, cereals, marshmallows, and pom poms to represent plasma, red blood cells, white blood cells, and platelets. It helps students visualize the different components of blood and their functions.
Thermite	★★☆	★★☆	★★★	The thermite reaction produces molten iron by reducing iron(III) oxide with aluminum powder. Once ignited, the highly exothermic reaction releases intense heat and light, creating a dramatic classroom demonstration of redox chemistry.
Energy Stick Human Circuit	★★★	★★☆	★☆☆	The Energy Stick is a safe handheld circuit tester that lights up and buzzes when you complete a circuit by touching its electrodes. It demonstrates conductivity in people and materials, helping students explore conductors, insulators, and the idea of closed circuits.
Oscillating Clock Reaction	★★★	★★☆	★★☆	The Briggs-Rauscher reaction is a dramatic oscillating chemical reaction in which a solution alternates between amber and blue-black colors several times before settling into a final dark-blue state. The color changes are caused by the interplay of iodine species, hydrogen peroxide, malonic acid, starch, and a manganese catalyst.
Gravity Visualized	★☆☆	★★☆	★☆☆	Stretching fabric over a frame to create a “spacetime” surface lets students see how mass curves space and guides motion. By placing heavy and light objects on the fabric and rolling marbles, the class can model orbits, accretion, tides, and even visualize gravitational waves.
Nitinol Shape Memory Alloy	★★★	★☆☆	★★☆	Nitinol, a nickel-titanium alloy, demonstrates shape memory by returning to a pre-set shape when heated. Unlike ordinary wire, Nitinol “remembers” its original form and straightens itself when exposed to sufficient thermal energy.
Lycopodium Powder Fireball	★★☆	★★☆	★★★	Lycopodium powder, when ignited in a pile, burns slowly due to limited oxygen contact. When dispersed as a fine dust cloud and ignited, the vastly increased surface area causes rapid combustion, producing a dramatic fireball or small explosion.
Lemon Juice Invisible Ink	★☆☆	★☆☆	★★☆	Lemon juice is used to write a hidden message that becomes visible when heated with an iron.
Mentos and Diet Coke	★☆☆	★☆☆	★★☆	Dropping Mentos candies into Diet Coke causes a rapid release of dissolved carbon dioxide, creating a dramatic soda eruption. This is a physical reaction caused by surface roughness on the Mentos that accelerates bubble formation.
Flying Tea Bag	★☆☆	★☆☆	★★☆	An emptied tea bag is set on fire, and as it burns, hot air rises through convection. Once the bag becomes light enough, it is lifted into the air by the rising column of hot gases, demonstrating the principle behind hot air balloons.
Mousetrap Nuclear Fission	★☆☆	★★☆	★☆☆	An array of mousetraps loaded with ping pong balls is used to simulate a chain reaction, showing how one event can trigger many others in quick succession. The setup visually models nuclear chain reactions in a safe and dramatic way.
Breaking Glass with Sound	★★★	★★★	★★★	A thin-walled wine glass can be shattered by sound if it is exposed to a tone at its natural resonant frequency. When the sound drives the glass strongly enough, vibrations build until the glass breaks.
Standing on Balloons Without Popping	★☆☆	★★☆	★★☆	A student standing on a single balloon will pop it, but standing on a board supported by many partially inflated balloons spreads their weight and allows the balloons to hold without bursting.
Balloon Bed of Nails	★☆☆	★★☆	★★☆	A single nail easily pops a balloon because all the pressure is concentrated at one point. But when many nails share the load, the pressure is spread out, allowing a balloon (and by analogy, a person) to withstand much more force before popping.
Ping Pong Vacuum Cannon	★★★	★★★	★★★	A sealed tube is evacuated and a ping pong ball is placed near one end. When the near seal is ruptured, atmospheric pressure accelerates the ball down the evacuated tube with negligible air resistance, allowing extreme speeds that can puncture cans and thin plywood. This demonstration highlights gas pressure, Newton’s laws, and the role of drag.
Air Pressure Breaks a Ruler	★☆☆	★☆☆	★★☆	A ruler placed on the edge of a table with covered by a piece of paper can be broken by a swift strike.
Floating Ping Pong Ball	★☆☆	★☆☆	★☆☆	A ping pong ball can be suspended in the air stream of a hair dryer. This demonstrates Bernoulli’s principle, which explains how differences in air pressure keep the ball floating and stable in the moving air.
Freezing Flowers With Dry Ice and Alcohol	★★★	★★☆	★★★	A mixture of dry ice and isopropyl alcohol creates a very cold liquid at around -90 °C, which can instantly freeze flowers, candy, or fruit, making them brittle and easy to shatter.
Air Cannon Smoke Rings	★★☆	★★☆	★★☆	A large trash can fitted with a flexible plastic membrane can be used to create giant smoke rings. Striking the membrane sends a vortex of air through a hole, which can be made visible with smoke to demonstrate air movement and Bernoulli’s principle.
Giant Pendulum	★★★	★★☆	★★☆	A large pendulum suspended from the ceiling demonstrates conservation of energy by swinging out and back to its starting point near the instructor’s chin, never exceeding its original height. The dramatic demonstration shows that mechanical energy is conserved and that potential energy converts to kinetic energy and back.
Flying Optical Illusion	★★★	★★☆	★☆☆	A large mirror creates the illusion that a person’s leg reflection is actually their other leg, making it appear as though both legs lift off the ground and the person is flying.
Genie in the Bottle Rope Trick	★★☆	★☆☆	★☆☆	A hidden ball inside a bottle creates friction against a rope, making it appear that the rope is magically suspended in the bottle. This trick demonstrates how frictional forces resist motion between surfaces.
Non-Burning Money	★☆☆	★★☆	★★☆	A dollar bill or paper soaked in a 50/50 alcohol-water solution is ignited. The alcohol burns brightly, but the bill remains unharmed because the water absorbs the heat and prevents the paper from reaching its ignition temperature.

Materials
★☆☆ Easy to get from supermarket or hardware store
★★☆ Available in most school laboratories or specialist stores
★★★ Requires materials not commonly found in school laboratories

Difficulty
★☆☆ Can be easily done by most teenagers
★★☆ Available in most school laboratories or specialist stores
★★★ Requires a more experienced teacher

Safety
★☆☆ Minimal safety procedures required
★★☆ Some safety precautions required to perform safely
★★★ Only to be attempted with adequate safety procedures and trained staff