What kind of sounds do you think nails will make? Do you think all nails will make the same sound?
What do you know about making predictions? What is the difference between a prediction and a guess? Talk about your ideas with the class, parent or friend.
Look at the nails. Think about the sound they could make. How do you think the nails will sound when tapped with a pencil? Will they all sound the same, or will each one sound different? Why? Write your predictions in your notebook.
Place the nails on the sponge and test your predictions by tapping each nail with a pencil. To make the clearest sound, you will want to tap quickly but not too hard. Take turns (if you have a partner) so both of you can listen.
Tak about and compare words you could use to describe the sounds you heard. Did one nail sound "higher" than the others? Did one sound "lower"? Write in your notebook words to describe the sounds.
Review your predictions and compare them with the actual sounds you heard.
Finally, think about how the size of the nail seemed to affect the sound it made. Write some of your thoughts in your notebook.
Ideas to Explore:
Select a nail of a different size or one made of a different material. Predict how this new nail will sound compared with the others. Test your prediction.
Find a book about musical instruments and read about the xylophone. Where did it come from? What different types of xylophones are there?
Sound Site ©1999 Science Museum of Minnesota