In a four-year study of the effect of class size on pupil outcomes in a sample of 36 primary schools in Hong Kong, it has been found that there are few positive differences in attainment between classes set at less than 25 pupils and those of normal size averaging 38. Three cohorts of pupils were studied. In Cohort 1 pupils spent 3 years in small…

Prior research has established the potential for achievement gains from attending smaller classes. However, large statewide class-size reduction (CSR) policies have not been found to consistently realize such gains. A leading explanation for the disappointing performance of CSR policies is that schools are forced to hire additional teachers of…

This brief summarizes findings on class size from over 25 years of work on the Tennessee Student Teacher Achievement Ratio (STAR) randomized, longitudinal experiment, and other Class-Size Reduction (CSR) studies throughout the United States, Australia, Hong Kong, Sweden, Great Britain, and elsewhere. The brief concludes with recommendations. The…

Evidence from Project STAR has suggested a considerable advantage of being in small classes in early grades. However, the extra benefits of additional years in small classes have not been discussed in detail. The present study examined the additional effects of being in small classes for more than 1 year. We find that once previous grade…

The researcher conducted a nonexperimental study to investigate and analyze the influence of reduced class sizes, intensity (all day and every day), duration (five years), and heterogeneity (random class assignment) on the Head Start Fade effect. The researcher employed retrospective data analysis using a longitudinal explanatory design on data…

This paper introduces an empirical strategy to estimate dynamic treatment effects in randomized trials that provide treatment in multiple stages and in which various noncompliance problems arise such as attrition and selective transitions between treatment and control groups. Our approach is applied to the highly influential four year randomized…

Despite evidence from the USA that children in small classes of less than 20 do better academically there is still a vociferous debate about the effects of class size differences in schools, and considerable gaps in our understanding of the effects of class size differences. This article summarises results from the most complete UK analysis to…

It is widely assumed that increasing the number of teaching assistants (TAs) in the classroom will be beneficial to children, and this is one important aim of the recently implemented Workforce Agreement. But there are still significant gaps in knowledge about many aspects of their deployment and impact. The Class Size and Pupil-Adult Ratios…