Acceleration - the rate of change of velocity, or how fast an object or person speeds up.

Air -  a form of matter made up of a mixture of invisible, odorless, and tasteless gasses. Mostly made of the gasses oxygen and nitrogen, this mixture surrounds the earth, and allows us to breathe.

Air resistance - when friction slows the movement of something moving through the air. The friction of the atmosphere will slow and eventually stop an object in motion.

Balanced Force - forces that are in contact, moving in opposite directions, but are equal in size. 

Catalyst - something that changes the speed (speeds up) of a chemical reaction or change without being used up at the end of it or being permanently changed.

Exothermic reaction - a chemical reaction in which less energy is needed to break bonds in the reactants than is released when new bonds form in the products. During an exothermic reaction, energy is constantly given off, often in the form of heat. All combustion (explosive) reactions are exothermic reactions.

Friction- occurs when two surfaces move over each other. Air resistance and water resistance are friction forces caused by the movement of something through the air or the water.  The friction of the atmosphere will slow and eventually stop an object in motion.

Force - a push or pull.  Nothing can move unless a force is applied to it. Force can be used to start or stop an object in motion or cause it to change direction. Force is measured in units called newtons (N)

Gravity - the force of attraction between any two bodies.  It increases with increasing mass of the bodies and decreases if they are further apart.

Hoverboard - a means of transport that travels just above the surface of the ground, using fast-moving air to force the board upward, reducing friction.

Inertia - a property of matter by which it remains at rest or in motion in constant speed, going in the same straight line unless acted upon by some external force.

Invisible force - forces acting upon our environment that cannot be seen. These forces  include things like gravity, friction and air resistance, to name a few. These are also considered non contact forces.

Kinetic Energy - the kind of energy in moving things

Liquid - a form of matter between solid and gas. Liquid particles have more space between them, so they are not fixed in position. The attraction between the particles in a liquid keeps the volume of the liquid constant. The movement of the particles causes the liquid to be variable in shape. Liquids will flow and fill the lowest portion of a container, taking on the shape of the container but not changing in volume.

Mass - the amount of matter or substance that makes up an object

Matter - the material that something is made up of. There are four natural states of matter: Solids, liquids, gasses and plasma

Newton (N) - How force is measured. A unit of force.

Potential energy - energy that is stored up in an object due to its position (is it on the top of a hill?), electrical charge (how much battery charge does it have before you turn it on?), or mass (or, more simply, how much does it weigh? Items with more mass have more gravitational pull).

Simple Machine - A simple machine is a device used to make work easier. The six types of simple machines are: incline plane, wedge, screw, lever, wheel/axle, and pulley.

Solid - A form of matter that we can observe that holds its shape in everyday situations.

Sound Waves -  vibrating forms of energy that are made of molecules. These vibrations look like waves. Sound waves can travel through solids, liquids and gasses. The vibrations from sound waves cause our ears to send signals to our brains to create sound.

Weight Distribution -  when the weight of something is spread out equally. The bed of nails is an example of how weight distribution works.

Visible Force - a force that occurs when two or more objects come in contact with one another. A force in which the contact can be seen, such as kicking a ball with your foot, or pushing or pulling a door with your hand.

Volume - how much room something takes up.

Ist Law of Motion - A body at rest wants to stay at rest. A body in motion wants to stay in motion. An object that is sitting at rest will stay at rest, and an object that is in motion will stay in motion until a force acts upon it. This is also called The Law of Inertia.

2nd Law of Motion - The greater the force the greater the acceleration. The greater the mass, the greater the force needed to move the object. Force = mass times acceleration.

3rd Law of Motion - For every action there is an equal and opposite reaction.

Balance - tricks that involve placing an object (or even person) on some part of the body - hand, foot, head, shoulder, etc. The object has only one point of contact. If the person doesn’t move to keep it under control, the object will fall. A successful balance uses balanced forces.

Clubs - a weighted juggling prop with a head and handle, For more advanced jugglers. Not to be confused with bowling pins which are much heavier and are weighted differently.

Clown - a person who makes people laugh by using tricks, movements or sounds. Clowns used to use a lot of makeup and special costumes, but these days, clowns can be without makeup and can be dressed like normal people. It is the ability to make people laugh that makes someone a clown.

Clown College - A school run by Ringling Brothers and Barnum and Bailey, where students learn the art of clowning, including things like makeup application, sewing costumes and physical skills such as stilt walking, unicyling, juggling, tumbling, and more. 

Human Cannonball - a circus act where a performer is shot from a large cannon and flies across the arena, landing on an airbag or net. This act primarily demonstrates Newton's 3rd Law of Motion.

Juggling Balls - Typically bean bags or weighted balls, approximately in diameter used for juggling, preferably with enough weight for your hand to close around easily when catching them.

Gag - a joke or short skit that a clown performs for an audience.

Pie - Used in clown gags, these pies are made of shaving soap and are typically pushed by one clown into another clown’s face.

Scarves - lightweight, gauzy squares of material used for juggling, best used indoors for beginning jugglers. Juggling scarves use the science of air resistance to make juggling easier.

Teeterboard  - a circus act where the weighted force of a person lands on one end of a teeterboard (it kind of looks like a playground teeter-totter), catapulting the person waiting on the opposite end of the teterboard. The teeterboard act uses potential energy, kinetic energy and all three of Newton's Laws.

Trapeze Artists - Made up of fliers and catchers, these circus performers fly through the air as they swing on bars hanging from ropes. When they let go, they move through the air, transferring from one swinging trapeze to another on the opposite side.