1Clobeck C.L.Campbell S.E.&Bjorklund.S.A.(2000)Gronping in the dark:What college students learn from group projects.The Journal of Higher Education.71(1)
2Fuchs L.S.&Associates(2000).Effects of workgroup structure and size on student productivity during collaborative wrok on complex tasks. The Elementary School Journal, 100 (3).
3Eggen, P. &. Kauchak, D. ( 1994 ). Educational psychology: Classroom connections. New York Macmillan College Publishing Company.
4Arends, R. I. (1991). Learnign to teach.McGraw-Hill, Inc.
5Quina, J. (1989). Effective secondary teaching:Going beyond the bell curve. New York: Happer &.Row, Publishers.
6Collette, A. T., &,. Chiappctta, E. L.(1989), Science instruction in the, middle and .secondary schools, Columbus. OH: Merrill Publishing Company.
