A compelling case for preschool provision is made by Ted Melhuish, lead evaluator of the UK flagship prevention program Sure Start children’s centres. In the current edition of Science he looks at Art Reynolds’ large long-term study which considers the highly disadvantaged African-American children, which is reported in the same edition of Science and in yesterday’s edition of Prevention Action [See: What an effective intervention seems to falter].

But as Melhuish points out, the findings from the Chicago Longitudinal Study, which Reynolds has been studying, complement many small scale US studies that demonstrate pre-schools contributing to better educational, occupational and social outcomes for disadvantaged children. Melhuish points to Jim Heckman’s work showing the cost-effectiveness of early years interventions.

This evidence is reasonably well known. Less well reported but as impressive are studies from European countries. The universal pre-school ecole maternelles, introduced in France during 1960s and1970s, eventually reached between 90 and 100 per cent of three- and four year-olds. The French evidence points to intervention having a sizeable effect on children’s success in school and later in the labour market.

Since children from poor socio-economic backgrounds fared disproportionately better than those from better off families, the French pre-schools helped close the gap between rich and poor. Melhuish quotes similar examples from Switzerland and Norway.

Now there is evidence from the global South and from emerging economic powers, particularly in South America and Asia. It is claimed that pre-school has pushed up primary school achievement by 0.23 of a standard deviation in Argentina. China is putting high quality early years provision at the heart of its policies to boost the quality of its workforce.

The challenge, however, is maintaining quality. When P. Sammons and colleagues in the UK compared low- and high-quality pre-school they found former had no effect. Robert Pianta has argued that publicly funded pre-school typically narrows the gap between rich and poor by five per cent and not by its 50 per cent potential. Why? Because too often delivery is of insufficient quality.

References:
Ted Melhuish, PreSchool Matters: Evidence grows that starting preschool at age 3 or 4 can produce benefits decades later, Science, 5th July 2011, Volume 333

Jim Heckman, Skill Formation and the Economics of Investing in Disadvantaged Children, Science, Volume 312, 2006

P. Sammons, K. Sylva, E. Melhuish, I. Siraj-Blatchford and others, Influences on Children's Attainment and Progress in Key Stage 2: Cognitive Outcomes in Year 6, Department for Children, Schools and Families, London, 2008

Robert Pianta, W. Steven Barnett, Margaret Burchinal, and Kathy R. Thornburg, The Effects of Preschool Education: What We Know, How Public Policy Is or Is Not Aligned With the Evidence Base, and What We Need to Know, Psychological Science in the Public Interest August 2009 10: 49-88,