Behavioral and Brain Functions, an open source journal, recently published research on the effects of white noise on 51 school aged children. The results indicated that playing white noise during school helped to significantly improve the attention spans of normally inattentive students. On the other hand, the students who were normally attentive showed a significant decline in memory abilities as the white noise was turned up. The researchers recommend that cognitive performance can be improved in inattentive children with the use of background white noise.
Reference: Goran B. W. Soderlund, Sverker Sikstrom, Jan M. Loftesnes, Edmund J. Sonuga-Barke The effects of background white noise on memory performance in inattentive school children Behavioral and Brain Functions 2010, 6:55 (29 September 2010)