In the current study, two experiments were carried out: the first tested the development of derivational root and word-pattern morphological awareness in Arabic; the second tested morphological processing in Arabic spelling. 143 Arabic native speaking children with normal reading skills in 2nd, 4th and 6th grade participated in the study. The…

Italian has regular spelling-sound correspondences; however, assignment of lexical stress is unpredictable. Sensitivity to stress neighborhood information was investigated by constructing three types of three-syllabic nonwords: nonwords with word-endings characterized by a strong neighborhood of dominant stress words (dominant), nonwords with…

Experimentation skills are a central component of scientific thinking, and many studies have investigated whether and when primary-school children develop adequate experimentation strategies. However, the answers to these questions vary substantially depending on the type of task that is used: while discovery tasks, which require children to…

To assess the efficacy of guided oral reading as a remedy for low-achieving readers, two experiments were conducted in the early grades of primary school. In the first, poor-reading students were randomly divided between two treatment groups and a control group. In treatment groups, the intervention was delivered one-to-one, either in a repeated…

Background: Cluster-randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…