noisli - site and free app
This site or app could be used to boost your own productivity and concentration at work and at home. It could also help students avoid distraction while they work independently on computers, laptops, or handheld devices, each student choosing his or her own sound combination. You could even play something for the whole class during silent reading time to help buffer small, distracting noises.
calm -site and free app
Calm.com, a relaxation therapy website, gives the stressed-out masses a place to relax on the Internet.
The website provides two- and 10-minute guided relaxation sessions, accompanied by pleasing backgrounds and gentle music.