REFERENCES

• Driver , R. and Scanlon , E. 1989 . Conceptual change in science . Journal of Computer Assisted Learning , 5 ( 1 ) : 25 – 36 .
   Google Scholar
• Hewson , P. A case study of the effect of the metaphysical commitments on the learning of complex scientific theories . Paper presented to the 1980 AERA Annual Meeting . Boston , USA.
   Google Scholar
• Lawson , A.E. 1992 . What do tests of formal reasoning actually measure . Journal of Research in Science Teaching , 29 ( 9 ) : 1029 – 1051 .
   Web of Science ®Google Scholar
• Levy , O. 1994 . Teaching 5th and 6th grade students statistical thinking skills Unpublished M.Sc Thesis , Jerusalem : The Hebrew University of Jerusalem . (In Hebrew)
   Google Scholar
• Metz , K. 1995 . Reassessment of developmental constraints on children's instruction . Review of Educational Research , 65 ( 2 ) : 93 – 127 .
   Web of Science ®Google Scholar
• Posner , G.H. , Strike , K.A. and Gertzog , W.A. 1982 . Accommodation of a scientific conception: toward a theory of conceptual change . Science Education , 66 ( 2 ) : 211 – 227 .
   Google Scholar
• Royer , J.M. , Cisero , C.A. and Carlo , M.S. 1993 . Techniques and procedures for assessing cognitive skills . Review of Educational Research , 63 ( 2 ) : 201 – 243 .
   Web of Science ®Google Scholar
• Shayer , M. 1987 . Data processing and science investigations in schools . Research Papers in Education , 1 ( 3 ) : 237 – 253 .
   Google Scholar
• Shayer , M. and Addey , P.S. 1992 . Accelerating the development of formal thinking in middle and high school students . Journal of Research in Science Teaching , 29 ( 1 ) : 81 – 92 .
   Web of Science ®Google Scholar
• Sweller , J. 1994 . Cognitive load theory, learning difficulty, and instructional design . Learning and Instruction , 4 ( 4 ) : 295 – 312 .
   Google Scholar