Background School-based service-learning is a teaching strategy that explicitly links community service to academic instruction. It is distinctive from traditional voluntarism or community service in that it intentionally connects service activities with curriculum concepts and includes structured time for reflection. Service learning, by connecting education to real world issues and allowing students to address problems they identify, may be particularly efficacious as it increases engagement and motivates students, in particular students who might not respond well to more traditional teaching methods. Objectives The main objective was to answer the following research question: What are the effects of service learning on academic success, neither employed, nor in education or training (NEET) status post compulsory school, personal and social skills, and risk behaviour of students in primary and secondary education (grades kindergarten to 12)? Further, we wanted to investigate study-level summaries of participant characteristics (e.g., gender, age or socioeconomic level) and quality of the service learning programme. Search Methods We identified relevant studies through electronic searches of bibliographic databases, governmental and grey literature repositories, hand search in specific targeted journals, citation tracking, and Internet search engines. The database searches were carried out in November 2019 and other resources were searched in October 2020. We searched to identify both published and unpublished literature, and reference lists of included studies and relevant reviews were searched. Selection Criteria The intervention was service learning which can be described as a curriculum-based community service that integrates classroom instruction (such as classroom discussions, presentations, or directed writing) with community service activities. We included children in primary and secondary education (grades kindergarten to 12) in general education. Our primary focus was on measures of academic success and NEET status. A secondary focus was on measures of personal and social skills, and risk behaviour (such as drug and alcohol use, violent behaviour, sexual risk taking). All study designs that used a well-defined control group were eligible for inclusion. Studies that utilised qualitative approaches were not included. Data Collection and Analysis The total number of potentially relevant studies constituted 13,719 hits. A total of 37 studies met the inclusion criteria. The 37 studies analysed 30 different populations. Only 10 studies (analysing nine different populations) could be used in the data synthesis. Eighteen studies could not be used in the data synthesis as they were judged to have critical risk of bias and, in accordance with the protocol, were excluded from the meta-analysis on the basis that they would be more likely to mislead than inform. Five studies did not provide enough information enabling us to calculate an effects size and standard error, and one study did not provide enough information to assess risk of bias. Finally, two clusters of studies used the same data sets, resulting in an additional three studies we did not use in the data synthesis. Meta-analysis of all outcomes were conducted on each conceptual outcome separately. All analyses were inverse variance weighted using random effects statistical models incorporating both the sampling variance and between study variance components into the study level weights. Random effects weighted mean effect sizes were calculated using 95% confidence intervals. We carried out a sensitivity analysis to examine the impact of correcting for clustered assignment of treatments. Main Results The 10 studies (analysing nine different populations) used for meta analysis were all from the United States. The timespan in which included studies were carried out was 33 years, from 1980 to 2013; on average the intervention year was 2007. The average number of participants in the analysed service learning interventions was 937, ranging from 18 to 3556 and the average number of controls was 927, ranging from 20 to 3395. At most, the results from three studies could be pooled in any of the meta-analyses. All the meta-analyses showed a weighted average that favoured the intervention group except the pregnancy outcome. None of them was statistically significant except the weighted average of the two studies reporting math test results. The random effects weighted standardised mean difference was 0.09 [95% confidence interval (CI): -0.02 to 0.21] for students' general grade point average; 0.04 (95% CI: -0.08 to 0.16) for reading; 0.21 (95% CI: 0.09 to 0.33) for math; 0.03 (95% CI: -0.10 to 0.16) for days absent from school; 0.13 (95% CI: -0.14 to 0.40) for self-esteem; 0.07 (95% CI: -0.04 to 0.18) for locus of control. The random effects weighted odds ratio was 1.05 (95% CI: 0.63 to 1.74) for pregnancy and 0.96 (95% CI: 0.74 to 1.25) for sexual risk behaviour. In addition, a number of other outcomes were reported in a single study only. There were no appreciable changes in the results as indicated by the sensitivity analysis. We did not find any adverse effects. Authors' Conclusions In this review, we aimed to find evidence of the effectiveness of service learning on students' academic success, personal and social skills, and risk behaviour. However, the evidence was inconclusive. We found only few randomised controlled trials and the risk of bias in the included non-randomised studies was very high. All available evidence used in the data synthesis was US-based. The majority of studies available for meta-analysis reported on a very limited number of outcomes; in particular few reported results on students' academic success even though the outcome was collected. Further, the majority of studies used in the meta-analyses reported implementation problems. These considerations point to the need for more rigorously conducted studies performed outside the United States, reporting a larger number of outcomes. It would be natural to consider conducting a series of randomised controlled trial with specific allocation to implementation of high-quality service learning as guided by the eight standards: (1) Meaningful service, (2) Link to curriculum, (3) Reflection, (4) Diversity, (5) Youth voice, (6) Community partnerships, (7) Progress monitoring and (8) Sufficient duration and intensity. Specific attention would also have to be paid to stringency in terms of conducting a well-designed randomised trial with low risk of bias and ensuring that the sample sizes are large enough to enable sufficient power.
