 Hi everyone, my name is Ruben and I'm a librarian here at the San Francisco Public Library. For today's STEM Challenge, I'm going to show you how to make straw rockets. Before we get started, do we all know what STEM means? In case you don't, STEM is an acronym for Science, Technology, Engineering, and Math. So what makes straw rockets a STEM activity? Well, it has to do with propulsion, which is the action or process of pushing or pulling to drive an object. So for example, you might be familiar with engines or motors, which propel things like vehicles and maybe some other things that we see every day. In this project, your power source is going to be your lungs. So let's get started. First, I'm going to show you the materials you need to make your straw rocket. First thing you need is a rocket ship template, just like this. You need a couple of different straws. First, you need a Boba straw, kind of a thick round straw. You need a standard drinking straw. This, you're going to need some tape and some scissors, just regular scissors will work. And optional, you can use some colored pencils or crayons or whatever you'd like to design your rocket ship. So let me show you how it's done. Let me move these things out of the way. And I'm going to start with a template that I've already colored in. So this is the optional step. You can color in a template if you like, or you can leave it blank, just like one of these. So that's your choice. First thing I'm going to do is cut out the rocket ship from the piece of paper. OK, there we go. All right, the next thing that you're going to do, you're going to flip it over to the side where there's nothing showing and you're going to get your Boba straw. So with that Boba straw, you're going to lay it against the backside of your rocket, just like this. Because what you want is a length of straw that is about the same length as your rocket ship. So I'm going to kind of just take it right here and snip it and just make sure it doesn't fly off the table. Or now that I've got a little mark, I'm just going to pick it up and cut it. There we go. So I've got a small little length of straw that's about the same length as my rocket ship, roughly. The next thing I'm going to do, I'm going to take some tape and I'm going to take a piece and cover one end of the straw, like that, you see? And I'm going to push it down and it doesn't have to be perfect. So we just want to make sure that it's completely flat against the edge of the straw. And I like to take an extra length and kind of wrap it around the straw. So you just to keep it, make it a little smoother. So there we go. So now I have an end with no air that can escape out this side. So I'm going to take this and put it back down and I'm going to need some more tape. So I am going to take some tape so that I can tape the straw down to the back of the rocket ship. So I'm going to do this. It's probably going to take a few strips and that's OK. So there's one side and I like to do it kind of on two lengths of the straw just for extra stability. OK, there we go. So now I have a rocket ship with kind of a straw tube on the back of it. Now, the next thing I'm going to do is take my other straw, my black straw, and that straw slides right in to your Boba straw just like that. Now I'm going to blow this, but then I'm going to talk to you a little bit about it with this other one. So now that you've got your straw rocket, it is ready to fly. So when you're ready to fire it, you just put it in your mouth and blow. So it'll be like this. You see it flies off just like that. So now that you've built your straw rocket, you can try launching it from different angles. So for example, you can start it here and shoot it. You can turn your rocket higher and higher and higher. And when you're doing that, you can think about what is going to make this rocket shoot further? Is it when I hold it at this angle? Is it when I hold it at that angle? This angle? So it's something to experiment with. You know, what is that perfect launch angle? That's for you to try to figure out. You can also make your own design. You don't have to use the rocket template. You can make your own anything and do the same thing that we just did. You put your Boba straw on the back of it, close it up, and fire it with your straw. And you can experiment with all sorts of designs. What is going to fly further? What's going to stay in the air longer? Have fun with it. And that's all for today. So thank you so much for joining me and hope you get to shoot some rockets into space.