Effects of intervention to improve at-risk fourth graders' understanding, calculations, and word problems with fractions

The purposes of this study were to (a) investigate the efficacy of a core fraction intervention program on understanding and calculation skill and (b) isolate the effects of different forms of fraction word-problem (WP) intervention delivered as part of the larger program. At-risk 4th graders (n = 213) were randomly assigned at the individual level to receive the school's business-as-usual program or 1 of 2 variants of the core fraction intervention (each 12 weeks, 3 sessions/week). In each session of the 2 variants, 28 min were identical, focused mainly on the measurement interpretation of fractions. The other 7 min addressed fraction WPs: multiplicative WPs versus additive WPs. Children were pre- and posttested on fraction understanding, calculations, and WPs. On understanding and calculations, both intervention conditions outperformed the control group, and the effect of intervention versus control on released fraction items from the National Assessment of Education Progress were mediated by children's improvement in the measurement interpretation of fractions. On multiplicative WPs, multiplicative WP intervention was superior to the other 2 conditions, but additive WP intervention and the control group performed comparably. By contrast, on additive WPs, there was a step-down effect in which additive WP intervention was superior to multiplicative WP intervention, which was superior to control. [This paper was published in "Elementary School Journal," v116 n4 p625-661 Jun 2016 (EJ1103953).]