Science ideas for young children: Sand castles

Having a day at the beach? Experiment with sand castles to learn about nature and science.

Building sand castles can be fun and frustrating. The journal Nature did some research into “How to construct the perfect sandcastle.” You can engage children in an engineering conversation during a day at the beach by asking questions. Carefully thought-out questions can help children think about the science and engineering needed to build a sand castle. Here are some questions Michigan State University Extension recommends asking children when building a sand castle.

  1. What makes the “best” sand castle? Height? Sturdiness? Level of detail? How can you change the sand to be the best?
  2. Why doesn’t dry sand build a sand castle? If you pour dry sand out of a bucket, what shape does it make? Can you force it to make a different shape?
  3. How much water is the right amount for a sand castle? Take several buckets of sand (make sure the buckets are the same size) and add different amounts of water to each bucket. Which one will be the best for building sand castles? Experiment and find out. See which bucket of sand can build the highest castle. Do different amounts of water allow you to create more detailed castles? Are some more durable?
  4. What is the best way to protect your castle from the waves? Build your castle close enough to the water that some waves hit the castle. Then build barriers between the castle and the waves to see which is the most effective. Are some barrier shapes better at dissipating the waves than others? Is it better if you put sticks or rocks in the barrier? What distance should the barrier be from the castle?
  5. Does a moat protect your castle? Make predictions as to how a moat will affect the stability of a castle. Will it make it fall in sooner or absorb potentially damaging waves?
  6. Can you reinforce your castle? Does including other material such as rocks or sticks make your castle stronger? Why or why not?
  7. How much weight can your sand castle support? Try building a tower out of sand and place a small cup at the top of it. How many pennies can it hold before it falls over?
  8. Can you build a sand bridge? Why or why not?
  9. What do you think will happen to the sand castle as it dries? Will it get stronger or weaker? Why?

These experiments can be done within a family, in a day-care setting, as part of school activities, a 4-H club or with any group working with young children. Take a trip to the beach as part of a Pure Michigan adventure and engage in some science discussion.

Did you find this article useful?