In this simple STEM activity for kids learners will investigate how a balloon can be used as a simple speaker. They will blow up the balloon, tap it and listen to how to sounds travel through it. They will then discuss the outcome of their experiment and explain why the balloon speaker works in the way that it does. This activity could be used as a starter activity to introduce the concept of sound and how it travels, or as one of several activities within a wider scheme of learning focusing on sound. Activity: Balloon speakers This is one of a set of free resources developed to support the teaching of the primary national curriculum. They are designed to support the delivery of key topics within maths and science. This resource focuses on using a balloon as a simple speaker to amplify sound. What happens when you tap the balloon? What can you hear and feel? Why do you think this is happening? This is a quick and easy STEM activity that will take approximately 15 – 20 minutes. The engineering context Engineers must understand how speakers work in order to successfully design products that use them, such as phones, music players and TVs. Sound engineers must understand how sound can be amplified and transmitted from one place to another. For example, at a concert. Understanding how speakers work is a very important part of this. Suggested learning outcomes By the end of this exercise students will know that vibrations from sounds travel through a medium in the ear. They will also be able to use a balloon as a simple speaker and explain how it works. Lastly, they will understand how pushing air closely together affects the volume of sound travelling through it. Download the Balloon speakers activity sheets for free! All activity sheets and supporting resources are free to download, and all the documents are fully editable, so you can tailor them to your students’ and your schools’ needs. The activity sheet includes teacher notes, guidance, useful web links, and links (where appropriate) to the national curriculum in each of the four devolved UK nations; England, Northern Ireland, Scotland and Wales. Please share your classroom learning highlights with us @IETeducation

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