Geek my class — Bouncyballs.org is a noise meter for your class....
Teach Starter - How neat is this...monitor classroom noise level with virtual bouncy balls! It uses the microphone on your laptop, you can 'see' the noise level and so can your students!!
Monitor Classroom Noise with Bouncyballs.org - Classroom Freebies
Amazon.com: InnoGear Microphone Stand, Boom Scissor Arm Stand Webcam Stand for Microphone Webcam with Mic Shock Mount 3/8" to 5/8" Screw Adapter Windscreen Pop Filter Mic Clip Holder Ball Head Phone Holder :
Classroom Noise Monitor Apps That Teachers Will Love