What is you guys' opinion on catapults and the like?

Here’s a catapult you could build, if you have enough room at the science fair.

As for random knowledge:
Catapults were primitive artillery weapons that use elastic or gravitational potential energy to accelerate projectiles of any type on a balistic trajectory towards the enemy. Two types of catapults that greatly impacted galactic history were energy catapults, employed by the Gungan Grand Army to launch their energy ball ordnance at the Trade Federation Army during the Battle of Naboo in 32 BBY, and the catapults used by the Ewoks to launch their more primitive rock projectiles at the occupying Imperial force during the Battle of Endor.

Does the project have to be on weaponry? If not, I would do something along the lines of showing how wind farms and wave farms can save the world from energy depletion. Or, demonstrate how energy efficient washing machines work. I won two science fair blue ribbons back in the olden days and both had to deal with pollution abatement and removal. Whatever looming crisis seems to be foremost in the world at the time will be on the brains of the judges and they are likely to consider your project ahead of others if it is done properly.

Ohhhh….another hot topic lately is showing how urban farming is working. check this link Very, very cool and I think you could make a working model with no problem.

Here is the aquaponics link. this would be so cool to do! I have seen the working model and it is so neat. First prize here you come.

My opinion remains that my husband is not allowed to build and test one in the garden!....and the most detailed knowledge I have of catapults I got from Mythbusters

What about a trebuchet or ballista?

I know they worked well in the medieval times but I’m not so sure about their practicality in the 21st century. That’s about all I know of them.

Oh wait, when it comes to catapults, the Trebuchet was the badass out of all of them. I saw a Discovery channel program on it and that’s what they said – if you need a catapult of any kind, go with a Trebuchet first.

Wildflower- …the Mythbuster team rechristened theirs “The Tosser.”

How appropriate….!
my opinion on catapults remains unchanged :)

Thank You guys s o o o o much for the comments!

I am a fan of boiling oils…

Catapults are fun!

I did a high school physics project on the range obtainable by a basic lever arm catapult, and had a hard time controlling the experiment because it involved dropping a weight on the opposite end the projectile was on, and wasn’t secured very well. But I enjoyed it. I’d look at the assignment requirements closely and try to design the mechanism and experiment to match it.