Here's one paper; I'm sure there are others out there, too.
http://people.brunel.ac.uk/~hsstffg/preprints/chess_and_education.PDF
Edit - One more link:
http://www.iier.org.au/iier13/thompson.html
Edit 2 - Another:
http://www.geocities.com/chess_camp/taas4.pdf
Edit 3 - Another
http://www.vivacityinc.com/chess/BenefitsOfChess.pdf
Edit 4 - Another
http://www.chess.ca/misc2008/benefitsofchess.pdf