# How to Demonstrate Principles of Engineering, Stability & Gravity

Learn how to demonstrate engineering, stability and gravity principles using marshmallows with the instructions in this Howcast science project video.

### Transcript

Hey, guys. Thinking natural disasters.

When you think of natural disasters, there are several that come to mind. You have earthquakes, volcanoes, tornadoes, hurricanes. But, if I show you marshmallows, and I show you toothpicks, and tell you that we’re about to do an experiment that has to do with natural disasters, you’re gonna be, like, “Wait, what? Marshmallows and toothpicks, and natural disasters? But you.” Yeah, we’re going to do that, and I have a challenge for you. This is your challenge: I need you to get a bag of marshmallows, and you know what I love about this, is if your marshmallows ever get stale, the worst thing to do as a scientist is to throw them out. You can reuse anything, rather than making it into garbage.

Now, you have a challenge, and your challenge is this, can you create a multi-story structure, a structure, I think, that people can build? So, you have to make it multi-floored, which means more than one or two, I would say. And, here’s the kick, after you build it, it has to be standing. You’re not allowed to hold it up. It has to be free-standing and stable. Stable on the table. Gravity should not be knocking it down. Then, we’re going to simulate an earthquake. So, after you’re done, and you've made this really awesome structure, made out of only marshmallows and toothpicks, we’re going to shake the table, and we’re going to make an earthquake. And you can be, like, “Earthquake.” Just tremble and vibrate. And if your structure is still standing after 30 seconds of your simulated earthquake, you, my dear, are an engineer.

And check this out. Your structure’s actually gonna be three-dimensional, and all you need are marshmallows, and all we need are toothpicks. It doesn't matter if they’re the pointy type or the flat type, but, marshmallows are actually cylinder shapes. So, take a marshmallow, take a toothpick, put it through. You kinda have, it looks like you’re going to be working out with it, but you’re not. Now, think about how we can take this, and turn it into a really awesome three-dimensional shape. I’m going to start with this square, and then I’m going to build it up, and turn this square into a cube. Now I’m going to start going higher, just like this.

And the beauty about this experiment is, a bag of marshmallows is so inexpensive. Toothpicks, pretty much anybody has toothpicks at home. And, I can learn so many amazing concepts of engineering, building, gravity, center of gravity. You see, you really want this structure to have this amazing centered gravity, so that, If you really think about it, gravity’s always trying to knock you down. In fact, unfortunately, when we get a little older, you start to lean forward, because in your lifetime, your body has done nothing but battle gravity. Which is why our backs arch as we get older.

But, now look. I just made a three-dimensional cube. This is exactly one floor high. But the challenge is, could you create multi floors. And, as you get it to go higher and higher, it has to be stable. Stable on the table. You do not want it to be not balanced. The rules are you’re not allowed to hold it up. This is a challenge. And you’re only allowed to use toothpicks; you’re not allowed to get Scotch tape. Okay? That’s the challenge. And, as you can see already, mine is starting to lean. Gravity’s always pulling on it. I’m only gonna make mine three toothpicks high, just because I don’t need to make it bigger. That’s gonna be your challenge. Then, I’m gonna simulate an earthquake, and then, I’m gonna see if my structure is still standing.

And, there are other things that you can do, actually, to try to make your structure more stable. Questions like, ‛What happens if you added toothpicks across the squares?’ Something like this. Would this help? Would this help? Science is all about asking questions. Test them, and see what happens.

That’s two toothpicks high, and now I’m gonna go three toothpicks high. And by the way, if you don’t have marshmallows, you can actually use gumdrops. My whole point of this is, you can build and learn about structure and engineering and earthquakes, using any materials that you have at home. Uh-oh, gravity. Stop. There we go, it does get a little harder as you get higher. You gotta realize that, and you guys are gonna get frustrated. Starts to look like the leaning Tower of Marshmallows. And, I’m just going to put my toothpicks across the top, and then I’m gonna shake the table, and it’s earthquake time.

Will my structure still be standing? Will it fall? If it does fall, what could I do differently to try to get it to stay up? Science is all about asking amazing questions. Right now, it’s standing, and I am about to make an earthquake. As I hit the table, the table’s gonna shake, and let’s see what happens to my structure.

Still standing. It’s stable on the table. Marshmallows, toothpicks, your challenge, make a multi-story building, make it taller, shake the table, make an earthquake, and see if it’s able to still be standing.

I did it, can you?