Mrs. Grad's 1st grade finished up their lesson on sound waves last week. To demonstrate, they did a telephone cup experiment. First, students tried communicating when the string was loose, which didn't work. Then, they made the string tight between them, which worked. They had already learned that materials make sounds when they vibrate, so they discussed how the sound waves can travel through the string to the other end when tight. The kiddos were telling jokes to each other through the cups
|
|