The main purposes of this study were to test the effects of teaching at-risk 4 th graders to provide explanations for their mathematics work and examine whether those effects occur by compensating for limitations in cognitive processes. We randomly assigned 212 children to 3conditions: a control group and 2 variants of a multi-component fraction intervention. Both intervention conditions included 36 sessions, each lasting 35 min. All but 7 min of each session were identical. In the 7-min component, students were taught to provide high quality explanations when comparing fraction magnitudes or to solve fraction word problems. Children were pretested on cognitive variables and pre/posttested on fraction knowledge. On accuracy of magnitude comparisons and quality of explanations, children who received the explaining intervention outperformed those in the word-problem condition. On word problems, children who received the word-problem intervention outperformed those in the explaining condition.Moderator analyses indicated that the explaining intervention was more effective for students with weaker working memory, while the word-problem intervention was more effective for students with stronger reasoning ability.Key words: supported self-explaining, fractions, intervention, moderator, working memory,
reasoning EXPLAINING WHY FRACTION MAGNITUDES DIFFER-4
Supported Self-Explaining during Fraction InterventionCompetence with fractions is important for advanced mathematics learning and success in the American workforce (National Mathematics Advisory Panel [NMAP], 2008;Geary Hoard, Nugent, & Bailey, 2012;Siegler et al., 2012). Yet understanding about fractions and skill in operating with fractions are difficult for many students (National Council of Teachers of Mathematics, 2007; NMAP;Ni, 2001). The NMAP therefore assigned high priority to improving fraction instruction. The focus of the present study was on the effects of intervention to enhance at-risk learners' performance on fractions at fourth grade. Our main purposes were to isolate the effects of intervention focused on teaching children to explain why fractions differ in magnitude and to examine whether effects accrue by compensating for limitations in cognitive processes.In this introduction, we describe why teaching children to provide high quality explanations may enhance understanding of the explained content and provide a rationale for the supported self-explaining approach we took. We also discuss how self-explaining without such scaffolding can be cognitively demanding and why the approach we took may compensate for limitations in the cognitive resources many children with histories of poor mathematics learning experience. Finally, we describe the theoretical orientation of the multi-component intervention program in which our explaining intervention component was embedded.
Explaining Why Fractions Differ in MagnitudeA major purpose of the present study was to isolate the effects of intervention teaching children to provide sound explanations regard...