The purpose of this analysis was to assess whether effects of 1st-grade mathematics intervention apply across the range of at-risk learners' initial skill levels. Students were randomly assigned to control (n=213) and 2 variants of intervention (n=385) designed to improve arithmetic. Of each 30-minute intervention session (48 over 16 weeks), 25…

This study explored factors that are associated with calculation development among 176 children at-risk for learning difficulties. Data were collected on working memory, language, non-verbal reasoning, processing speed, decoding, numerical competence, incoming calculation, SES, and gender at the beginning of 1st grade and on calculations over 4…