We want students to ask questions and classroom environment lively and fear free. 
Asking questions make us think, reason out.

Motivate students to ask questions. 

Ask students to type their questions about sound,  "What they want to learn/know about sound?" in the assessment tool box. They can type more than one question.

Categorize the recorded questions in the the three categories- Production of sound, Characteristics of sound, Propagation of sound. 

It is not necessary that the answer will be provided to the students, but they should be involved in the process of finding answer.