The debate over what counts as credible evidence often occurs on a methodological level (i.e., about what technical applications of systematic inquiry provide believable, justifiable claims about a program). Less often, it occurs on an epistemological level (i.e., about what ways of knowing are appropriate for making claims about a program). Even…

Background and purpose: Studies of education and learning that were described as experiments have been carried out in the USA by educational psychologists since about 1900. In this paper, we discuss the history of randomised trials in education in the USA in terms of five historical periods. In each period, the use of randomised trials was…

Background and purpose: Studies of education and learning that were described as experiments have been carried out in the USA by educational psychologists since about 1900. In this paper, we discuss the history of randomised trials in education in the USA in terms of five historical periods. In each period, the use of randomised trials was…

Challenge the Gap (CtG) is a school collaboration programme designed by Challenge Partners that aims to break the link between disadvantage and attainment. The main components of CtG are: (1) after-school workshops drawing on published research and evidenced practice; (2) focused in-school interventions with a selected cohort of disadvantaged…

This paper describes a randomised controlled trial conducted with 10 secondary schools in England to evaluate the impact and feasibility of Fresh Start as an intervention to help new entrants with low prior literacy. Fresh Start is a synthetic phonics programme for small groups of pupils, here implemented three times per week over 22 weeks. The…

U.S. social programs, set up to address important problems, often fall short by funding specific models/strategies ("interventions") that are not effective. When evaluated in scientifically-rigorous studies, social interventions in K-12 education, job training, crime prevention, and other areas are frequently found ineffective or…

Studies of small-scale "model" early-childhood programs show that high-quality preschool can have transformative effects on human capital and economic outcomes. Evidence on the Head Start program is more mixed. Inputs and practices vary widely across Head Start centers, however, and little is known about variation in effectiveness within…

U.S. social programs, set up to address important problems, often fall short by funding specific models/strategies ("interventions") that are not effective. When evaluated in scientifically-rigorous studies, social interventions in K-12 education, job training, crime prevention, and other areas are frequently found ineffective or…