LEVERS from SIMPLE MACHINES

Trebuchets, or catapults were used in Middle Ages to breakdown castles and great big walls of fortresses.  Often times winning the big battles of enemies, these leverage machines were created in a style of  either counter weighted or counterpoised.  Before gunpowder became popular, trebuchets were the powerful tools to be wreckoned with! (get it?? wreck the castle?? Purposeful misspelling..ha-ha).  Flinging an object that can weight up to 350 lbs. is bound to do much damage.  Taking over fortresses and defeating the enemy was the name of the game back then.
You may be thinking..."What does this have to do with Science?"  Well, simple machines were used for so many advances of human kind that we just couldn't skip the infamous lever.  Naming some simple levers in our homes, we see that objects like tweezers, bottle openers, tab on a can of soda, some doorknobs (our storm door) have made our lives much more efficient and less stressful. (unless you accidentally pop the finger ring of a soda can off; been there! done that!)
Here are some pictures of Austin making a homemade counter weighted trebuchet out of balsa wood, wood glue, matchbox, rubber band, and round pencil.  He found that the counter weights needed to be increased (double to triple amounts) to get better propulsion of his object across the room.