Students become involved in learning through hands-on experiences, and integrating science into other areas of study such as Arts Education. Transmitting devices can be made by students. Have students build their own private telephone line. Using two cans punch a hole in the end of each just large enough to poke a string through. Repeat with the other end and the second can.
Students become involved in learning through involvement in the study of how sound travels.
Divide the class into working groups assigning each group a different task. Provide large chart paper, markers, possibly old magazines and scissors, etc. This could be done by more than one group using differing comparatives. When groups share and display their work, other class members can be encouraged to add to the lists. Students become involved in learning through working together.