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The effectiveness of volunteer tutoring programs

Additional Info

  • Authors: Gary Ritter, Ginger Albin, Joshua Barnett, Virginia Blankenship, George Denny
  • Published date: 2006-06-21
  • Coordinating group(s): Education
  • Type of document: Review
  • Title: The effectiveness of volunteer tutoring programs
  • See the full review:

Volunteer tutoring programs are intended to improve student performance, provide mentorship, and improve student self-esteem, as well as behavior. Despite the best of intention and effort, schools are not certain which volunteer tutoring programs are most effective. Therefore, we contend that a rigorous analysis of the extant literature regarding volunteer tutoring programs can provide schools with information about the most effective types of tutoring programs.


To assess the effectiveness of volunteer tutoring programs for improving the academic skills of student enrolled in grades K-8 in the USA, and to further investigate for whom and under what conditions tutoring can be effective.

Search strategy

A range of electronic social science databases were searched including Academic Search Premier; Primary Search; Professional Development Collection; Middle Search Plus; Psychology and Behavioral Sciences Collection; PsycINFO; Sociological Collection, ERIC (Education Resources Information Center), and Proquest Digital Dissertations.

Selection criteria

Only randomized field trials (in which a treatment was compared to a control group that did not receive the treatment) published from January 1985 to August 2005 were included in our review. We only included studies that included academic impacts, although other impacts could be part of the study (e.g. behavioral, emotional). We also only included programs that were used for students in grades K – 8, and programs where adult, non-professional (volunteer) tutors were used.

Data collection and analysis

Details on the methods and procedures (i.e., design, analysis, outcome measures), the intervention (i.e., duration, setting), and the subject samples (i.e., age, gender, ethnicity) were coded for each study to allow for analysis of outcomes for different types of volunteer tutoring programs and for different study characteristics. After we identified all outcomes measured in the included studies, we selected the appropriate effect size metric for the meta-analysis. We used Hedges’ unbiased estimate g of the standardized mean difference effect size statistic (the difference between the treatment and control group means on an outcome variable divided by their pooled standard deviations) for each outcome measure. When means and standard deviations were not reported, we attempted to estimate the effect sizes using the procedures recommended by Wilson and Lipsey (2001). When studies had multiple measures of an outcome, we computed a pooled mean of effect size.

Main results

The results of the review were based on the data from 1,676 study participants in 28 study cohorts in 21 research articles or reports. The analysis of these studies – most of which included relatively small samples – showed that volunteer tutoring programs can positively influence language and reading outcomes for students. We began by examining the overall effects of volunteer tutoring on student reading outcome measures. Twenty-five studies assessed reading measures of one type or another. The average effect of volunteer tutoring programs on reading outcomes for elementary students is 0.23. After removing one outlier study which disproportionately influenced by the overall result, we found an average effect size of 0.30. We also found several significant results in the meta-analyses of specific academic domains. The outcomes where volunteer tutoring programs made a significant difference were Reading Global (effect size = 0.26), Letters and Words (effect size = 0.41), Oral Fluency (effect size = 0.30), and Writing (effect size = 0.45). We found positive, but not significant, effects of volunteer tutoring on Reading – Comprehension and Mathematics. When we analyzed the reading outcomes separately by study characteristics, we found no significant difference in effect size by tutor type, grade level, or program focus. Highly structured tutoring programs had a significantly greater effect on global reading outcomes than programs with low structure, but not on the other outcome types. The difference in effect sizes between studies published in journals and non-published studies was not statistically significant. Other tests of publication bias also suggested the included studies were an unbiased sample.

Reviewers’ conclusions

This review does not suggest that there are any particular volunteer tutoring models that should be recommended for immediate adoption for schools and districts across the country. Rather, we can conclude from the analysis that these programs can positively influence important reading and language sub-skills for young students. The results are substantial – approximately one-third standard deviation. In the end, the results of this analysis should serve as one important piece of evidence used by policymakers and educators who are deciding whether to employ volunteer tutoring as a strategy to improve academic skills for young students. As educators across the country work to meet adequate yearly progress goals in state accountability systems, and as they seek affordable ways to offer additional services to students at risk of not meeting annual academic goals, it would be worthwhile to consider structured, reading-focused volunteer tutoring programs as strategies to improve reading and language skills.

See the full review

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