Abstracts - Earli

might be explained by their longer school education. This fact underlines the infantile educationimportance to the posterior learning performance of the children.Illusion of linearity: Effect in multiple-choice problemsMiroslav Rajter, Gfk, CroatiaVesna Vlahovic-Stetic, Faculty of Philosophy, Department of Psychology, CroatiaNina Pavlin-Bernardic, Faculty of Philosophy, Department of Psychology, CroatiaThe aim of this study was to examine if there is a difference in successfulness of non-linearproblems solving between younger and older, male and female students and between a group ofstudents who had an offered linear solution for non-linear problems and a group that was notoffered a linear solution. For the requirements of this study three lists of mathematical problemswere constructed. Form A contained five non-linear problems, and for every problem five answerswere offered. Among these five answers, one was a correct solution; one was incorrect linearsolution, while the remaining solutions served to reduce the probability of guessing. Form B wasidentical to Form A, but a linear solution was not offered in it. Problems in the Form C wereclassical proportionality problems with five offered solutions. One half of participants were askedto solve forms A and C, and the other half to solve forms B and C. A convenience sample of highschool students was examined. The sample consisted of 112 first grade (N=52) and fourth gradestudents (N=60), 53 girls and 59 boys. There were no differences between participants in thesolving of linear problems. The older students were more successful in the solving of non-linearproblems than the younger ones. The students in the group without the linear solution were moresuccessful than those who had an offered linear solution. The interaction effect of age and solvingsituation showed that older students were somewhat better than younger students when a linearsolution was offered, but that difference was even larger when a linear solution was not offered.The results suggest that methods of education should be re-examined if we want the students tolearn different models that can be applied successfully in the school and real-life situations.Studying the fidelity of implementation of tasks in classroom settings: High-level mathematicstasks embedded in ‘real-life’ contextsGabriel Stylianides, University of Pittsburgh, USAAndreas Stylianides, University of Oxford, United KingdomDespite the increased attention to ‘real-life’ mathematics tasks and also the importance of faithfulimplementation of high-level mathematics tasks for improved student outcomes, little research hasexamined the factors that may influence the fidelity of implementation of the special category ofhigh-level mathematics tasks that are embedded in real-life contexts. In this paper, we take a steptoward addressing this need for research. First, we propose an analytic framework for describingand explaining the fidelity of implementation of different kinds of tasks (not necessarily high-levelor mathematical) in classroom settings. Then, we use this framework to analyse the decline in thecognitive demands of a high-level, real-life mathematics task in the seventh-grade classroom of anexperienced teacher, receiver of a prestigious teaching award. Our analysis shows that the declinein the cognitive demands of the task resulted from the interaction, during the implementationphase of the task, between main features of the task (namely, its motivational aspects and its highcognitive demands) and the social practices that regulated the functioning of knowledge in theclassroom. Finally, we discuss the significance of the analytic framework and of our findings fortheory and educational practice.– 464 –