How to Build Straw Rockets, Catapults, and AP Rockets


This article is designed to help you understand the essential terms which can help you to comprehend the principles behind motion and equip you with problem-solving skills. You will see how energy is related to motion and how engineers and scientists use these concepts to design complex systems such as rockets. Use these pointers when building your straw rockets, catapults, and AP rockets. 

1. Science Concepts

Force and Motion

Force is basically a push or a pull. It is measured in Newtons. Motion is a movement and results from a push or a pull. Thus, if you apply force on an object it will gain motion and start moving. The rate at which the object is moving is its velocity and is measured in Meters/Second. 


If something is pushed in one direction, an equal force is generated in the opposite direction. This force moving in the opposite direction is what is called thrust. Thrust is the force which drives rockets and certain types of airships. When you will be building your straw rockets or even experimenting with AP rockets, you will be utilizing the principle of thrust. 

Newton’s Laws

Newton’s laws have helped scientists and engineers to better understand motion. The straw rockets you will be building will use this principle to move in the air. These laws are 3 and are interrelated.

1. The first law: A body in a static position or in motion remains in that state unless an external force is applied on that body. For instance, if you don’t apply any force on your AP rockets, they will remain in a static state and will not move. The same applies to moving objects. If you don’t apply a certain force on the object, such a moving object will move in that given direction continually. 

But there are natural ways through which such a body cannot continue moving forever. These forces include gravity and frictional force which make the moving object to eventually come to a halt. 

2. The second law: The rate of change of motion of a moving body is directly proportional to the force causing such a change and takes place in the direction of the force. To understand this, look at the path followed by a stone once you throw it using catapults. It moves almost at a straight line, then it starts to get closer to the ground until it hits the ground. 

At the point of throwing, the major force is the one which you exerted when you threw the stone. But as it goes further from you, it encounters other forces such as air friction which reduces its speed and then gravitational force which pulls it to the ground. 

3. The third law: Action and reaction are equal and opposite. For instance, rockets move by taking advante of the thrust which is generated when air is pushed at the rear side of the rocket. The force pushing the rocket forward is equal and opposite to that generated by the air forced out at the rear side of the rocket. 

Center of Gravity/Pressure

The center of gravity is the point either inside the body or outside the body from which gravitational pull appears to be applied from. 

Potential Energy

Potential energy is unused energy. For instance, an object hanging from the top of a building has a potential energy equivalent to the distance between the ground and the point where it is hanged. If released, then this potential energy will be converted to motion thus gaining kinetic energy. 

Projectile Motion

Projectile motion is the motion which is followed when a body is thrown horizontally. Due to gravity and air friction, this object will not follow a straight line but a curved path. This curved path is the projectile motion followed by the moving object. 

2. Technology Concepts

Problem Solving

Problem-solving is the process through which one identifies a problem and tries to come up with solutions which will solve such a problem. This is an important skill in technology and engineering. 

Pneumatic systems

These are systems which utilize pressure to achieve certain movements or accomplish specific tasks. 


A system is a set which consists of several parts working together to accomplish a bigger task. All these different parts work in coordination to achieve a collective function performed by the system. A failure of one part will affect the performance of the system. 


Calibrations are marks which are used to indicate certain quantities and measurements. When creating your straw rockets, you will need to calibrate different parts to ensure that they fit into one another. Without calibration and measurement, it will be difficult to achieve your desired dimensions. 


Systems are composed of different sets and parts working to achieve a bigger function than what a single system could have achieved. 

Historical Perspectives

When building systems like the AP rockets, you will need to understand the past and learn how people in earlier years used to build those systems. This understanding is important in helping you shorten the design process and give you clues which will help you reduce design mistakes. 

Data Collection Processes 

Data collection processes are the steps which you will take to gather data about your project. You may get some of this data from books, from testing your straw rockets, and also from observation. 


Construction is the process through which you build your project until it takes shape and performs as required. It will involve putting different parts together, ensuring that they work properly and that they are strong enough to resist breake. 

3. Engineering Concepts

Aeronautical Engineering

This is a branch of engineering which deals with how objects move in the air. 


Prediction is the process through which you make accurate guesses from the data which you have. To accurately predict whether your project will work, you need to follow strict procedures and ensure that each part works reliably. 

Data Analysis and Prediction

Data analysis involves the rearrangement of data and manipulation of the data to bring up useful patterns. These patterns which have been derived from data analysis are used in predicting how the system will perform. 

Technology Design Modelling

Technology design modeling involves the creation of working models which are representative of the real system. This process is important in testing the system before it is even built. 

4. Maths Concepts


These are numbers which indicate the size, the quantity, and the intensity of something. Examples of quantities which can be measured include distance, volume, and weight. 

Coordinate Geometry and Transformations

Coordinate geometry is a branch of geometry which defines the position of an object using a set of numbers. Transformations are the different changes which can be done on shapes and objects on the coordinate plane. 


Symmetry is a mathematical term which indicates that an object or a shape has exact parts or parts which are proportional to one another. 


This is a branch of Maths which majorly deals with angles, their relationship with one another, and the planes forming a triangle. It also includes the functions of different angles and the principles governing different triangle shapes. 

Data Analysis

Data analysis involves applying certain mathematical functions to data to see if they will create useful patterns and trends. These trends and patterns are then analyzed to help better understand the concept being studied. 


An angle is formed when two planes meet. Angles are important in measurement and a good understanding of how angles form is key in designing working projects. 

Statistics Collection/Graphs

Once you collect data, it can be processed to create useful statistics. You can collect data over virtually anything and use such data to analyze patterns and changes. Graphs are the most common methods which are used in data analysis. 

5. Life Skills/Career Links

Sound Engineering

Sound engineering is the study of how sound moves in the air, water, and in solids. This discipline is crucial for those who wish to understand the various aspects of sound transmission and sound manipulation. 

Atmospheric Sciences

This is the study of the atmospheric gases, the effects different systems have on the atmosphere, and the effects of the atmosphere on these systems. Atmospheric sciences help us understand and predict short-term weather changes and also understand how different systems can change the climate. 


A physicist is a scientist who has specialists in physics. Such a person has a thorough understanding of how physical systems work and how they relate to energy. 

Environmental Science

This is a study which integrates different disciplines such as biology, physical sciences, social science, and other multiple disciplines to help better understand the environment and how different human activities affect the environment. 

Problem Solving

Problem-solving is an important skill. You will need this skill irrespective of the discipline which you are in. It will need you to be creative, be able to identify the core problem and generate ideas on how to solve the problem. 

Competition and Assessments on Designing Air Rockets to Travel the Farthest

This competition is important. It will help you improve your design skills and boost your creativity. It’s also important in enhancing your analytical skills and is bound to keep you interested. Competitions are excellent ways to learn from your colleues and together challenge each other to better understand the design concepts. 


Leave a Reply

Your email address will not be published. Required fields are marked *