Some of our favorite activities to do on inside days are simple STEM challenges. This straw boats engineering challenge is so easy and simple, but it’s also engaging and fun. On rainy days we like to construct straw boats inside and then take them outside to float in the puddles! For an added challenge it’s fun to experiment to see how many pennies we can get our boats to hold before they sink.

A fun and easy STEM challenge for kids. See how many pennies a straw boat can carry before it sinks in this awesome straw boats engineering challenge.

Getting Ready

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We headed into the kitchen to complete our drinking straw boats engineering challenge since it gets a little wet. It took just a few minutes to gather the following supplies:

  • Drinking straws
  • Scissors
  • Hot glue gun and hot glue
  • Bowl full of water
  • Pennies

I gave each child 5 straws and asked them if they could construct a straw boat that holds the most pennies.

Before we got to work, my eight-year-old son thought it would be a good idea to verify that straws actually float. He threw a few straws into the bowl of water and confirmed that they do. Then he threw a few pennies in the water to verify that they sink. I asked him why straws float and pennies sink. He decided that straws float because they trap air in the center.

The kids thought about the design of their boats for a few minutes and then got to work. It was really fun to watch their creative process!

A fun and easy STEM challenge for kids. See how many pennies a straw boat can carry before it sinks in this awesome straw boats engineering challenge.

Straw Boats Engineering Challenge

My five-year-old trimmed all of her straws and then glued them together side by side to make a long neon pink boat. She tested it several times and found that she could pile 6 pennies on it before it sank.

A fun and easy STEM challenge for kids. See how many pennies a straw boat can carry before it sinks in this awesome straw boats engineering challenge.

My son worked hard to trim his straws to construct his boat. He had a good idea to use the bendy part of the straw on the end so that he could modify his boat if needed.

After several tries the most his boat held was 5 pennies. He was a little disappointed after all the work and planning he put into it. He used some of his extra straw pieces to make a keel to see if he could balance the boat and stabilize it better.

A fun and easy STEM challenge for kids. See how many pennies a straw boat can carry before it sinks in this awesome straw boats engineering challenge.

I was really impressed to watch the kids think of creative solutions. They bent the straws, added pieces, and flipped the boat upside down to see if it could hold more pennies. The boat that held the most was surprisingly my five-year-old’s inelegant design!

The design of the boats definitely evolved as the kids discovered problems and experimented to fix them. It was also a great lesson in balance as the kids quickly learned that they had to add pennies to the middle of the boat first and then onto each side in turn.

A fun and easy STEM challenge for kids. See how many pennies a straw boat can carry before it sinks in this awesome straw boats engineering challenge.

The straw boats engineering challenge was an awesome way to spend a fun and educational afternoon with the kids. We’ll definitely be doing this one again! Be sure to scroll down for several more STEAM ideas for a rainy day or an afternoon inside.

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A fun and easy STEM challenge for kids. See how many pennies a straw boat can carry before it sinks in this awesome straw boats engineering challenge.

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