ORGANIZING WHOLE-CLASS DISCUSSION IN MATH EMATICS LESSONS - EFFECTS OF PRESENTING A PROBLEM WITH ANSWER ALTERNATIVES

The present study examined differential effects of whole-class discuss ion beginning with a problem, with and without answer alternatives, on its developments and cognitive consequences in the case of adding fra ctions with different denominators; 289 4th- and 5th-graders from six elementary schools were used as subjects. Results indicated that : (1) almost all students with or without alternatives figured out the corr ect answer through the discussion before being given feedback from the experimenter; (2) in the process of the discussion the students in Gr oup Without Alternatives made more remarks including explanations, que stions and counterarguments, especially those about the correct soluti on than students in Group With Alternatives; (3) the students in Group Without Alternatives tended to perform better in the transfer test. T he inferiority of Group With Alternatives in the acquisition of transf erable knowledge was interpreted as due to the lack of effective divis ion of labor based on partisan motivation where rival answer alternati ves were easily refuted in discussion. Strength and weakness of the ab ove two types of discussion and their possible flexible uses are discu ssed.