C4 practical: Sliding whistle support
Another cheap experiment (as long as you have a computer). The whistles can be bought from a toy shop or Ebay, I use some nice wooden ones that cost about £1 each. The only other thing you need is a computer with Audacity installed, this is a free programme that is well worth getting to know, if your computer doesn't have a microphone then you'll need one of them too. The method described on the worksheet simply...