@book{69107,
	author = {Krajcik, Joseph S. and Czerniak, Charlene M.},
	title = {Teaching science in elementary and middle school classrooms :},
	publisher = {McGraw-Hill, },
	year = {2003      },
	address = {Boston, MA : },
	edition = {2nd edition},
	note = {Revised edition of: Teaching children science, c1999.}
}