Sound Uncovered is a great, free app from here that is made by Exploratorium  We're beginning to use it in science and topic work where we're continuing using an ICT lab-free environment.

The Prompt sheet below is for the children who prefer a very structured way of going about things. The other children will have white boards etc to explore and revisit the prompts on the IWB.

You're free to edit the sheets and the presentation as you see fit.