How to Make a Catapult for Your Science Project

Here’s a step-by-step guide on how to make a catapult for your science project. Follow these instructions and you’ll have a working catapult in no time!

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A catapult is a device that was used in ancient times to throw projectiles such as rocks and spears. Today, catapults are used for recreation and as weapons. They are also popular items to build for science projects. You can make a small, simple catapult out of materials you may already have around the house.

What is a Catapult?

A catapult is a simple machine that has been used for centuries to launch things into the air. Today, catapults are often used as toys or for science projects. Building a catapult is a great way to learn about physics and engineering.

There are many different types of catapults, but they all work using the same basic principles. The most important part of a catapult is the arm. The arm is attached to a base and has a bucket or cup at one end. To launch something into the air, you first put it in the bucket or cup. Then you pull back on the arm, which stretches a rubber band or spring attached to the arm. When you let go, the rubber band or spring contracts, making the arm swing forward and launch whatever is in the bucket or cup into the air.

You can experiment with different kinds of materials to see what works best for your catapult. Once you have built your catapult, you can use it to launch balls, paper airplanes, marshmallows… anything that will fit in the bucket or cup!

History of the Catapult

The first recorded use of the catapult was by the ancient Greeks in 399 BC. The Greek physicist Dionysus of Alexandria – who lived in the city of Alexandria in Egypt – invented the first catapult, which was called a ballista. The ballista was a large crossbow-like weapon that could hurl stones or other projectiles a great distance.

The Roman army later adopted the catapult as a standard weapon, and during the Middle Ages, catapults were used extensively in warfare. By the late medieval period, catapults had become very sophisticated weapons, capable of hurling heavy projectiles with great accuracy over long distances.

Today, catapults are still used occasionally in warfare (most notably during the Siege of Sevastopol in World War II), but they are more commonly found as toys or used in science experiments.

How Does a Catapult Work?

A catapult is a device that was used in ancient warfare to throw large objects at enemy fortifications or troops. Today, the word catapult can also refer to a device used to launch objects a great distance without the use of explosives.

There are many different types of catapults, but they all work according to the same basic principles. A catapult uses gravitational potential energy to launch its payload. The force that launches the object is generated by the weight of the object itself. In other words, the heavier the object, the more force it can generate.

The weight of the object is balanced on an arm that is attached to a fulcrum. The fulcrum is a point around which the arm can pivot. When the arm is released, it swings down and strikes a lever that transfers energy to the projectile. The projectile is then launched into the air.

The size and weight of the projectile, as well as the length of the arm and the position of the fulcrum, all affect how far and how accurately the projectile will be launched. By experimentally testing different configurations, you can find out which design works best for your purposes.

Types of Catapults

A catapult is a device that was used in ancient and medieval times to throw objects such as stones or arrows at targets. Today, the word “catapult” can be used to describe any device that launches something into the air. There are many different types of catapults, each with its own unique design.

The most common type of catapult is the trebuchet. Trebuchets were first used in warfare in ancient China. They were later adapted by the Europeans during the Middle Ages. Trebuchets work by using a counterweight to swing a large arm, which hurls an object from one end of the arm through the air.

Another common type of catapult is the ballista. Ballistas were first used by the Greeks in warfare. They work by using tension to launch objects through the air.

The onager is another type of catapult that was used in ancient times. Onagers launch objects through the air using tension, like ballistas. However, they are powered by humans or animals, instead of by weights like trebuchets.

The sling is a simple type of catapult that has been used since ancient times. Slingshots work by propelling an object through the air using tension. The object is placed in a cup or pouch at one end of two cords or straps. The other ends of the cords are held in each hand, and the object is then hurled through the air by swinging the arms forward and releasing one end of the cord or strap.

Today, catapults are often used for fun rather than for warfare. Many people build homemade catapults as science projects or as toys for children to play with.

Building Your Own Catapult

In this project, you will learn how to build a simple catapult using only a few household materials. By doing this project, you will gain an understanding of the basic physics principles involved in the design and operation of a catapult.

You will need the following materials for this project:

1. scissors
2. 1 meter of string
3. 2 wooden dowels, each 30 cm long
4. 1 plastic bottle with a capacity of 500 ml
5. masking tape
6. A4 paper
7. ruler
8. pencil
9. stapler
10. Catapult base (see instructions below)

To make the catapult base, you will need:

11. 2 cardboard tubes, each 10 cm long
12. 4 rubber bands
13. hot glue gun and glue sticks


1. Cut two 10 cm lengths from each cardboard tube. These will be the supports for your catapult base

Supplies Needed

You will need the following supplies to make your catapult:
-Two clothespins
-One rubber band
-One popsicle stick
-One plastic spoon
-One rubber band

Step-by-Step Instructions

science project, you will need to make a catapult. This can be a very simple or very complex project, depending on your materials and your design. The following instructions will show you how to make a simple catapult using common household materials.

You will need:
-A sturdy piece of cardboard
-A rubber band
-A ruler or other straight edge
-A sharp knife or scissors

1. Cut a rectangle out of the cardboard. It should be about 8 inches wide and 10 inches tall.
2. Fold the rectangle in half lengthwise.
3. Use the straight edge and knife to cut a slit in the center of the long side of the rectangle, about 2 inches from the top and bottom.
4. Slip one end of the rubber band through the slit at the top of the cardboard rectangle. 5. Stretch the rubber band around to the bottom slit and slip it through. 6. Tape the rubber band in place at both slits so it is stretched across the inside of the cardboard rectangle. 7. Cut two triangle shapes out of the remaining cardboard, each with a base that is 2 inches wide and 3 inches tall. These will be your “arms” 8. Tape each arm to the outside of your rectangle, near the top, so that they are evenly spaced apart (see picture). 9

Testing Your Catapult

Now that you have built your catapult, it is time to test it! Here are a few things you will need to do to make sure your catapult is ready for the science fair.

First, you will need to test the tension in your elastic bands. The best way to do this is to stretch the band from one end of the catapult arm to the other. If the elastic band is too loose, the arm will not snap back up when you release it. If the elastic band is too tight, the arm will not be able to move at all. You will need to experiment with different tensions until you find one that works well.

Second, you will need to test how far your projectile goes when you launch it. You can do this by measuring the distance from where your projectile lands to where your catapult is standing. Again, you will need to experiment with different tensions and angles until you find a combination that gives you the best results.

Third, you will need to make sure your projectile is aerodynamic. This means that it should be shaped so that it cuts through the air easily. A good way to test this is to drop your projectile from a height of about 10 feet and see how far it goes. If it doesn’t go very far, or if it tumbles through the air, then it is not aerodynamic and you will need to redesign it.

Finally, you will need to practice using your catapult so that you can hit your target accurately on game day. The best way to do this is to set up a small target at a distance of about 10 feet away from your launching point. Then, take turns launching projectiles at the target until everyone has had a chance to practice.

Once you have done all of these things, you should be ready for the science fair!


Assuming you have followed the instructions in this guide, you should now have a working catapult that you can use for your science project. Congratulations!

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