Ask youngsters to recall from their Activity 2 discussions that radio waves travel in different lengths. Challenge teams to use their paper tuners to hypothesize the connection between sound wavelength and pitch. Once youngsters understand how their paper tuners work, ask them again what the numbers on a radio dial might mean. Give youngsters time to confer with their partners and agree on an explanation. The numbers on a radio dial are related to different-length radio waves.
Radio tuners work by focusing on radio waves of one specific length.
When you move the dial, you change the length of the radio wave that the radio picks up. Ask teams to share tuners and compare. It should, provided that the white noise has remained constant as well. For fun, the youngsters might adopt a certain paper length as their own radio station, naming it after their initials.