Introduction: Mini Siege Engines

Picture of Mini Siege Engines

Catapults - a classic and exciting engineering project that introduces students to fundamental ideas in physics and engineering like energy transformation, trajectory, and structural strength.

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Step 1: Materials

Please message me to report broken links. All of these materials are used in my other Instructables for kids, so your purchases can be used across multiple projects.

Step 2: Simple Catapult

Picture of Simple Catapult

To fire:

  • Load the projectile
  • Firmly hold down the front of the catapult
  • Pinch the cube under the basket and pull down, then release

Step 3: Leverpult

Picture of Leverpult

To fire:

  • Load the projectile
  • Hold down the base from inside the support structure
  • Firmly and quickly press on the lever. Do not strike the lever with a fist or other object or the hinge may break

Step 4: Slingshot

Picture of Slingshot

To fire:

  • Load the projectile
  • Firmly hold the front of the slingshot, or grasp the front of the slingshot as shown in the video
  • Pull back on the sling and release

Step 5: Advanced Ideas

Picture of Advanced Ideas

A straightforward advancement of the Catapult project is to add two baskets instead of one.

A wacky design, dubbed the Confused Catapult, incorporates two catapult arms onto one frame. Making catapult arms of different lengths allows the user to enjoy a wider range of trajectory options.


noles (author)2016-02-03

this is really cool

i wish it was buyable

olgamawougbe (author)2015-11-13

Hi - could you please list the materials for the catapult? For some reason the materials list shows up like this on this page:

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Thank you!

olgamawougbe (author)2015-11-13

Hi - could you please list the materials for the catapult? For some reason the materials list shows up like this on this page:

{"context":{"you-image":{},"spinner":{"jQuery110202310703694010483":521},"location":{"href":"","origin":"","protocol":"http:","username":"","password":"","host":"","hostname":"","port":"","pathname":"/editInstructable/publish/EF6GG4YH173P8OO","search":"","hash":""},"jQuery110202310703694010483":1,"gtmHasClickListenerTag":true,"b":{"sizzle-1444572116521":{"parentNode":["9933 46",149]}},"h":{}},"selector":"#editor-Object-185"}

Thank you!

LanceMakes (author)2015-10-11

Thanks for asking - I've added a materials section

dantey8a (author)2015-10-01

This is one of the things I have to do for a project that's due I think in 3 weeks, better get started.I think I'm gonna go with the slingshot my personal tool of mischief (^w^)

dantey8a (author)dantey8a2015-10-01

where do I find the instructions for the slingshot?

Robzikshi (author)2015-05-12

Love it

JenH1 (author)2014-12-11

Awesome! the projectiles really fly far!

bdoorah (author)2014-09-05

i love all your projects. It's really you teach simple machicens in your projects? pleas give me a hint. i am trying to figure it out :-(

cskinner7 (author)2014-07-02

Love all of these! Made them all in preparation for a class I am teaching. I figured out how to modify the Lever-pult into Torsion catapult by gluing regular cubes at the pivot point to your frame, and gluing drilled cubes below them. You can string a loop of nylon string through both holes (and the holes on the swing arm) and hold them with 1/2 craft sticks on both sides: Wind them up and you get a powerful torsion launch.

Also working on gravity swinging catapult and a trebuchet based on your framework. Pictures to come.

LanceMakes (author)cskinner72014-07-03

Hey, glad to hear that you've made good use of these lessons. I'd love to see some pictures of how you redesigned!

kurtwied (author)2013-11-27

all your projects are awesome!!:) i'm going to show my friends. where do you get the cubes you use? do you get them in large or small amounts?

LanceMakes (author)kurtwied2013-11-27

Thank you! You can buy the cubes here:

PoisonDartFrog (author)2013-03-29

To get corks, do you just save them from bottles or do you by them en masse from somewhere?

kurtwied (author)PoisonDartFrog2013-11-27

i buy them at hobby lobby.

kurtwied (author)2013-11-27

this is awesome!

kevmcd (author)2013-05-19

Quite simply splendid!

yapoyo (author)2012-09-07

I like this very much. How can I make this without the craft cubes? Are they really necessary?

LanceMakes (author)yapoyo2012-09-07

The cubes aren't necessary - I use them because it's what I use in all of my projects. I don't know what you have access to, so if I were you I'd rummage around my home for materials or visit a craft or hardware store. Good luck!

ynze (author)2012-06-21

And again congrats for being a winner in the Education Contest! Great project!

LanceMakes (author)ynze2012-06-21

Thanks! I am so psyched!!

poofrabbit (author)2012-05-25

Congratulations on being a winner in the Big and Small contest!

LanceMakes (author)poofrabbit2012-05-25

Why thank you - you're quite gracious. I've seen your positive feedback all over the site. Keep it up, and good luck in future contests :)

poofrabbit (author)LanceMakes2012-05-25

Awe you are so kind! I was excited to read you are in talks with instructables to sell a kit of one or more of your instructables! I think that is wonderful!! Your partner in education, poofrabbit

person% (author)2012-05-25


i used to enjoy making shooting thingies, i once made a thing similar to the skewer shooter, but it was aluminum (from cans) and it used a thick red rubber band and it can shoot sticks and pencils as well, but it wasn't as strong. i used to sell them as well. they don't reload very quickly and is not very accurate, so i use it close range. i also made a lot of similar shooters, one of then is a sliding one for extra power, and one that is about 2-3 centimetres long for hiding it from teachers.

i still think that the ones i just said do too much damage and gets me into a lot of trouble, so now i making paper wasp shooters.

rimar2000 (author)2012-05-01

Very fun for kids!

snoo (author)2012-05-01

this will be great for food fights!!!!!!!

batonas (author)2012-04-30

I love all your project, they are simple, afordable for anyone and great for children physic education, way more fun than reading a boreing book.
Keep up the good work.
P.S. you could sell diy sets for these project I think people would be glad to buy it.

LanceMakes (author)batonas2012-04-30

Wow, thanks for the kind words :) I've been talking with the Instructables HQ about selling the rubberband helicopters as kits - hopefully we'll see them in the store soon!

About This Instructable




Bio: I'm a writer, maker, and educator who's on a mission to better the world through hands-on engineering projects. Pledge on
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