Abstracts - Earli

accounted for the positive effect of including drawings on text comprehension and word problemsolving, four empirical studies were designed in order to check the effectiveness of two differentways for rewording word problems: conceptual and situational. Conceptual rewording wasdesigned to highlight the underlying semantic/mathematical structure of the problem, whilesituational rewording focused on the enrichment of the situational context in which the problemwas embedded, by making the temporal and causal structure of the situation explicit. Furthermore,the fourth study included drawings linked to each of the two kinds of rewording. Results showedthat conceptual aids, both textual and pictorial, were the most useful for children in solving wordproblems, while situational aids had very little effect on children’s achievement.Improving students’ evaluation of informal argumentsM. Anne Britt, Northern Illinois University, USAThree experiments investigated students’ ability to detect structurally flawed arguments. InExperiment 1, undergraduates frequently failed to notice when arguments were unsupported (claimwith no reason) or unwarranted (claim supported by an unrelated reason). A paper-and-penciltutorial improved performance only on the unsupported claim items. In Experiment 2a, the tutorialwas modified to include training to pay attention to the predicate of the claim. This tutorial waseffective in training students to detect unsupported arguments, but only immediate feedbackduring practice was effective in improving unwarranted arguments. Experiment 2b replicates theseresults with a web-based version of the tutorial. Future research will address the impact of learningto evaluate arguments on students’ comprehension and production of arguments.Imitative problem solving and the illusion of understandingIan Robertson, University of Bedfordshire, United KingdomIt has long been known that students often assume they understand a new topic better than theyactually do. This has been termed “surface” or “primary” understanding or the “illusion ofunderstanding”. This paper relates the illusion of understanding to the early processes of problemsolving characterised by imitation. Imitative problem solving is a subtype of analogical problemsolving where lower order elements are mapped from one source problem to the current targetproblem without being governed by a hierarchical understanding of the relations between theproblem elements. In spite of this, students often believe that they understand the example (thesource). I report two experiments where students assert a high level of understanding of anexample problem but little evidence that they can transfer that understanding to a new problem ofthe same type. The results are interpreted as showing that the illusion of understanding comesabout because students believe they can imitate the example problem but do not have enoughdomain knowledge to adapt the example to solve an exercise problem that varies from it.The effectiveness of problem based economics: A summary of two promising studiesJason Ravitz, Buck Institute for Education, USAJohn Mergendoller, Buck Institute for Education, USANan Maxwell, California State University, East Bay, USAThomas Smith, University of Illinois at Chicago, USAHelen Roberts, University of Illinois at Chicago, USAThis paper summarizes a problem based approach for teaching economics and the results of twostudies concerning the effectiveness of this approach, one in high school and one in college. Bothstudies aimed to compare the effectiveness of the problem based approach and traditional– 567 –