May 25 Activities

S/M- science and math combined! This week, we will be using different household liquids to clean pennies! This is a basic look at the science of chemistry, as we watch chemical reactions between the different types of liquid and the copper that pennies are made of. You can do some basic math with measuring the liquids out and timing how long you leave the pennies in the liquids. Remember, scientists ask questions, so that’s where we will start.

Ask yourself the following questions, and if you think of more, make sure to write them down!

Which of our liquids will clean pennies the best? Why do you think coins lose their shine? Would this experiment work on other coins, like nickels or dimes?

You will need a small cup or bowl and a label (a small piece of paper works) for each liquid. Try as many of the following liquids as you can find at home! Remember to ask an adult for help measuring and pouring these out! (As you pour, do some math! Discuss why we call the amount you are using ¼ of a cup. What does that mean? How many ¼ cups will fit in a full cup? How many cups would all of these liquids add up to if you put them all together?)

  • 1/4 cup of catsup
  • 1/4 cup of Cola (Pepsi or Coke)
  • 1/4 cup of apple juice
  • 1/4 cup of water
  • 1/4 cup of vinegar
  • 1/4 cup of vinegar + salt

Once you have each liquid in its own labeled cup, put one penny into each liquid. Make sure you start with pennies that are similarly dirty. That way, no penny starts this experiment cleaner than any other penny. Set a timer for ten minutes, and watch! Some liquids might be more exciting to watch than others. At the end of ten minutes, remove the pennies and wipe them off. Which liquid cleaned the penny best? Why do you think that was? Can you do some of your own research to find out why that liquid worked well? Try other coins in the same liquid to see if they clean other kinds of metals besides copper! Write your results down, and if you can, send a photo of your data to me at [email protected]


T/E- technology and engineering combined! This week, since the April showers have recently made a return appearance, we will design, build, test, and refine model umbrellas/rain shelters! You can use almost anything you find at home to build these: regular paper, muffin tin papers, coffee filters, popsicle sticks, paper or plastic cups, paper towel or toilet paper tubes, straws, waterproofing material (think vaseline) etc. The list goes on! Get creative! 

Your objective (goal) is to keep a toy dry underneath your umbrella or shelter as you pour water over it. Your umbrella should be able to stand by itself or hold itself up if you tape it to the toy you’re using. In other words, you can’t touch it once you start pouring water over it!  🙂 

As you gather your materials, ask yourself what makes an umbrella work? What shape is it? Why is it that shape? What is special about the material it’s made of? Why doesn’t the rain soak right through it? As you design your umbrella, try to answer those questions and do the same with whatever materials you are using. 

1. Before building, remember what makes a good engineer: Planning! DRAW your design first! Label it so you know what materials will go where, and how they will be kept together. 

2. Once you have drawn and labeled your design, you can build it. Keep track of how well it works when you slowly pour ½ cup of water over it. Look underneath: Is the top of your toy dry? If not, why not? Where did the water leak in? Did your umbrella hold up? If not, why not? Where did it fail? Address these questions and possible failures (remember that failing is incredibly important in science, and will help you make things better in the future!) and redesign your umbrella! Make notes or redraw it so you know WHAT you changed! Try again*! 

Please take photos or videos and email them to me at [email protected]! I would love to share your students’ creations with classes next year! 


*Having trouble? Here’s a website from a family that tried this challenge. Please don’t use this BEFORE you have tried your own designs out! STEM is all about original ideas, so we try not to give too many hints or directions to the students as they complete their STEM challenges. It’s amazing to see what the kids come up with on their own!