This data collection contains data from the second of four studies conducted on the associated ESRC grant (data from the other studies will be made available as separate datasets in ReShare). The purpose of this study was to investigate the extent to which various speeded-related processes constrain the development of working memory in children, and whether these processes mediate the relationship between working memory and academic attainment. To that end, a sample of 112 children aged between 5 and 8 years were given four tasks measuring speed-related aspects of working memory performance, specifically basic speed of processing, articulation speed, forgetting rates, and memory scanning speed. Experimental measures of short-term memory ('simple span') and working memory ('complex span') were also give, as were standardised tests of reading [Sentence Completion Forms of the NFER-Nelson (1998) Group Reading Test II Form A (6–14)] and mathematics [NFER-Nelson (1994) Mathematics 6–14].
