May 18 Activities
S/T- science and Technology combined! This week, we will be learning a little bit about solar energy, and using it to create some tasty treats! Before we build our device that will use solar energy to warm our snacks, please take a few minutes to watch the following short video. As you watch, try to write down three or more new facts you’ve learned from the video before moving on!
Now that we’ve watched the video and written down our facts, let’s build….(drum roll).... a solar energy powered S’mores Oven! We won’t be using fancy electrical solar panels, but we will be using an important part of how sunshine works: darker colored surfaces absorb more sunshine, or solar energy, and will therefore feel hotter to the touch than lighter colored surfaces. This is very important for making your solar energy oven work correctly! You will need the following:
A small box (like a pizza box, shoe box, or even a Kleenex box), black construction paper (remember, you can get basic supplies from KWH if you need to!), a piece of clear plastic wrap, aluminum foil, and some glue or tape.
- If your box does not have a lid that you can open, cut the top of the box around three of the four edges. Make sure to ask an adult for help!
- Tape or glue the aluminum foil over the inside of the lid of your box. This will reflect sunshine (solar energy) down into the main part of your box.
- Tape or glue the black construction paper to the bottom of the inside the box. This dark surface will hold the heat from the solar energy.
- Place graham crackers on the black construction paper, add a square of chocolate, and a marshmallow on top.
- Carefully stretch the plastic wrap over the S’mores you have just laid out on the construction paper.
- Angle the shiny foiled lid downwards, toward the plastic wrap. You may need a stick, fork, popsicle stick or something similar to prop under it to keep the lid pointing slightly downward.
- Now… place in a sunny spot and make sure the lid is reflecting the sunlight down slightly, but is not blocking direct sunlight from hitting the plastic wrap. Wait until your chocolate has melted and your marshmallows are soft, and ENJOY!
- Try to heat up some other things in your oven (pre-cooked or ready to eat items only)! Try warming some leftovers, melting butter, or seeing if you can make toast! There are all kinds of things you can try! What works best? What didn’t work? Remember that being a scientist isn’t always about things working… It’s just as important to find things that DON’T work. Keep a record of your trials, or better yet, write a “Solar Oven Cookbook” with recipes for foods that worked well and that you can heat up safely in your oven!
E/M- engineering and math combined! I hope you had a fun time with last week’s Egg Drop Challenge! If you drop an egg, it falls quickly and smashes when it lands. That is because an egg on its own has very little ability to slow itself down during its fall. It doesn’t have enough “air resistance.” Air resistance means something can use air to slow its fall. Things like butterfly wings, large leaves falling, and parachutes use air resistance to float gently through the air. This week, we’re going to build some parachutes to continue the fun! A parachute has three parts: the parachute itself, some strings, and the thing or weight being dropped gently to the ground. The parachute is very important, but will it work by itself, or are the other pieces just as important for a parachute to do its job? Let’s find out! You will need something lightweight but that will keep some air inside for the body of the parachute (a coffee filter, a paper towel, Kleenex, or a plastic shopping bag for example), four pieces of string, and something durable to use as a weight. This does not have to be heavy! It could be a person made out of pipe cleaners or clay or even a small stick or rock.
The basics of making a parachute are easy. Tie a piece of string (make sure they’re all the same length) to each corner of your parachute (if you’re using something square), or two to each of the handles if you’re using a shopping bag. If you’re using a coffee filter or something round, make sure your strings are tied directly across from each other. Tie the strings together underneath the parachute, and attach your weight. Now, drop it from a stool or a landing in your house, or a deck or porch if you’re outside. Does it float down slowly, or fall down quickly? If you can get your parachute to float down gently, you are ready for your next investigation! If you’re having trouble, try adjusting the length or placement of the strings, adding or taking away weight, adding “surface area” (making your parachute larger), or making sure there are no holes in your parachute.
Bonus investigations: Can a parachute work all by itself? Let’s find out! Try taking your strings and weight off and dropping your parachute again. Does it work? Let’s try some other things with your parachute! What happens if we make the strings longer? How about if the strings are shorter? How much weight is TOO much for your parachute? How much is too little? Finding these kinds of things out has been absolutely necessary for all kinds of parachute uses, like landing our rovers and probes on Mars and other planets! Did you know that NASA relies on parachutes to do that?? Check out some videos of parachutes in action!
This link will take you to YouTube, with a list of videos of different space-based parachute technology being tested!
Take some pictures (even better, videos!) of your projects and send them to me at firstname.lastname@example.org
I love to see what you come up with! Stay well, and hope to see you soon!