 Hi, welcome to the MIX, the Teen Center at the San Francisco Public Library. My name is Illiana and I am your humble host for our STEM Challenge Yourself series, where our marvelous librarians come up with science experiments that you can try at home. In today's challenge, you're going to learn about an early scientific tool and you can use it to help create an art project for everyday use. I will let our Challenge Master walk you through the science and the project. I think you're ready. Hello friends, I'm Mr. Joseph. Thank you for joining me. I'm very excited to share you one of my favorite summer projects that will get you excited about flowers and plants. Today we will be making a flower press. What is a flower press and why do we need to press flowers? Flower press is a scientific tool that plant scientists use to preserve flowers. Flower press is made from cardboard and papers that help absorb the moisture from the flowers as they dry. Flower press provides pressure and weight to flatten the flowers as thin or even thinner than a paper. To get us started, we need the following materials. We need three pieces of cardboard, about the size of a writing paper, that's 8 x 11.5, four pieces of paper about the same size of a writing paper, a ruler, a scissor, and make sure you use the age-appropriate scissor and a marking tool, it could be a marker or a pencil. Three rubber bands, and of course we need our live specimens, flowers and leaves. And I started out with my salad mix. Salad mix is a perfect place to start your experiment. To start, let's first make, let's draw and cut a square about the size of a pencil and that's about 8 inches, okay. And this, the first square we're making is our template. What is a template? A template is a drafting tool or a tracing tool that allows us to draw identical shapes. When I'm making a square, I like to work on the corner because I already have two edges here, we have one edge and then the second edge. So the third edge, I'm going to mark it, so the size of a pencil, it's about there and I'm going to use my ruler to draw a straight line. So I'm going to end up about here. You don't worry about being straight, being a perfect square, whatever square you create is going to be your template and you could just repeat that. And I'm going to connect that to this edge, so we have four edges, one, two, three, four. And that makes a square. Alright and now I'm going to cut my square, again it doesn't have to be a perfect square, don't you just love the sound of car boards when you're cutting. And there you have it, we have our first square that will serve as a template and how does a template work? So let me grab the rest of my materials, let's start with this one and I'm just going to put this on the corner right here and here's my other square. You can see we can repeat this identical shapes using a template. And for the papers, I think, okay, for the papers I could just stack them together and just draw one square from the top, okay, now we are ready to cut. I'm going to start with the papers because they're the easiest and I am being efficient here by cutting the stacks of paper so that I can have exactly four squares of papers made of various materials. Let me put my papers here and now we can cut the rest of our squares. And if you're having difficulty cutting your squares, always ask for an adult to help you and you don't have to rush it like them and there you have it. We have three squares made from car boards, four squares made from papers. Now we're going to make triangles out of these squares and to do that we need to draw a diagonal line from this corner to that corner, two, three, and finally our stacks of papers. Okay, we're almost there, we're almost done. So let me cut the square, I call this the sandwich triangles because it's like cutting a sandwich in half and it forms into stacks of triangles, okay, let me cut the car boards. Now you can also just keep the squares together and make your flower press into squares and the reason I'm doing triangles, there's a reason for it, I'll show you why, okay. And finally we have stacks of triangles made from car boards and papers. Now we are ready to assemble our flower press. So to begin we're going to start with one car boards and then layer it with two papers and then another car board, layer it with two papers and again it's like it's a sandwich of car boards, papers, car boards, papers, okay and voila. So let's start pressing flowers and so we're going to start with a one car board and one piece of paper and I have here my flowers that are and leaves and vegetables. I'm going to start with the leaves and just layer the leaves onto the paper and here's a tip, make sure they don't overlap and then cover that with a paper and stack that with another car board. So we're going to repeat the same thing, just going to do several here and I'm going to start with the flowers and for some flowers including you might have to do the petals instead but this one I'm going to do the entire flower, as you can see I'm just scattering, layering them on top, place the paper and then put some weight on it so it would start to blend alright and tie the corners, alright so wait for about five days and check your materials if they have dried or not, it takes about five to ten days to have a decent press flowers and leaves. Here are some samples of leaves that have dried by themselves and here are the samples of flowers that have dried and pressed with this flower press, okay and I'll show you some of the samples I have here that I produce using in process, okay and here are some flowers here, some California poppies here, some various leaves and here are some more samples and here are some more samples, okay so within five to ten days you should have a beautiful collections of flowers and leaves that you can use for creative and scientific purpose and thank you again for joining me and I have a happy plant science adventures, thank you and back to you Anna. Thanks Joseph, you all are well on your way of discovering visual records and what botanists use to preserve and record for science, I hope that you guys think about this experiment and maybe even use it for a bookmark in your future, be sure to check out this STEM challenge and other STEM challenges with resources full of tips and tricks at sfpl.org slash STEM challenge. Keep asking questions, keep observing, keep experimenting and stay STEM-tastic.