Big Brothers Big Sisters (BBBS)

Evidence Rating  
Evidence rating: Some Evidence

Strategies with this rating are likely to work, but further research is needed to confirm effects. These strategies have been tested more than once and results trend positive overall.

Health Factors  
Decision Makers
Date last updated

Big Brothers Big Sisters1 matches volunteer mentors with disadvantaged or at-risk youth mentees2. BBBS provides a mentoring program design to its network of independent agencies. The program focuses on building supportive relationships rather than addressing problem behaviors3. In the community-based version of BBBS, mentors spend about four hours per week engaging mentees in conversation and social activities for at least a year. In the school-based version, mentors meet mentees at their schools once a week during the academic year to engage in academic activities, conversation, and indoor games2.

What could this strategy improve?

Expected Benefits

Our evidence rating is based on the likelihood of achieving these outcomes:

  • Reduced delinquent behavior

  • Increased academic achievement

Potential Benefits

Our evidence rating is not based on these outcomes, but these benefits may also be possible:

  • Reduced aggression

  • Improved family functioning

  • Improved social skills

What does the research say about effectiveness?

There is some evidence that Big Brothers Big Sisters (BBBS) reduces delinquent behavior and improves school outcomes among mentees2, 3, 4. Additional evidence is needed to confirm effects.

Community-based BBBS can reduce youth’s aggressive behavior, improve relationships with parents, prevent minority boys from initiating illegal drug use, and improve girls’ academic performance3, 5. School-based BBBS appears to improve academic performance for youth whose matches remain intact for the duration of the school year6. Programs that recruit high school students as mentors (“High School Bigs”) have demonstrated better peer relationships among mentee students than non-mentored peers7. Youth entering the program with adequate parental relationships (neither very strong nor very poor) benefit the most from school-based BBBS8.

Research suggests that longer, closer matches yield stronger behavioral9, 10, mental health10, and academic effects11, 12, 13, possibly by enhancing the mentee’s relationships with teachers and parents14. Mentors who are college students appear less likely than other mentors to continue matches. Researchers recommend screening, training, and post-match support to ensure that matches continue15.

In school-based programs, mentoring meetings after school or during lunch time may have greater effects on academic outcomes than meetings held during school hours16. Researchers caution against using BBBS mentors primarily as tutors, as such matches appear less likely to endure15, and instead, recommend helping academically focused pairs connect interpersonally17.

How could this strategy impact health disparities? This strategy is rated likely to decrease disparities.
Implementation Examples

Big Brothers Big Sisters serves more than 400,000 youth, their families, and their mentors every year, and has served nearly 2 million youth over the past decade18.

Implementation Resources

BBBS - Big Brothers Big Sisters of America (BBBS).


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1 BBBS - Big Brothers Big Sisters of America (BBBS).

2 CEBC - California Evidence-Based Clearinghouse for Child Welfare (CEBC). Information and resources for child welfare professionals: List of programs.

3 PPN - Promising Practices Network (PPN). On children, families and communities.

4 OJJDP Model Programs - Office of Juvenile Justice and Delinquency Prevention (OJJDP). OJJDP model programs guide.

5 Child Trends-Lawner 2013 - Lawner EK, Beltz M, Moore KA. What works for mentoring programs: Lessons from experimental evaluations of programs and interventions. Bethesda, MD: Child Trends; 2013.

6 Herrera 2011 - Herrera C, Grossman JB, Kauh TJ, McMaken J. Mentoring in schools: An impact study of Big Brothers Big Sisters school-based mentoring. Child Development. 2011;82(1):346–361.

7 Herrera 2008 - Herrera C, Kauh TJ, Cooney SM, Grossman JB, McMaken J. High school students as mentors: Findings from the Big Brothers Big Sisters school-based mentoring impact study. Philadelphia: Public/Private Ventures; 2008.

8 Schwartz 2011 - Schwartz SEO, Rhodes JE, Chan CS, Herrera C. The impact of school-based mentoring on youths with different relational profiles. Developmental Psychology. 2011;47(2):450-462.

9 Gaddis 2012 - Gaddis SM. What’s in a relationship? An examination of social capital, race and class in mentoring relationships. Social Forces. 2012;90(4):1237-1269.

10 DeWit 2016 - DeWit DJ, DuBois D, Erdem G, Larose S, Lipman EL. The role of program-supported mentoring relationships in promoting youth mental health, behavioral and developmental outcomes. Prevention Science. 2016;17(5):646–657.

11 Park 2016a - Park H, Yoon J, Crosby SD. A pilot study of big brothers big sisters programs and youth development: An application of critical race theory. Children and Youth Services Review. 2016;61:83–89.

12 Bayer 2015 - Bayer A, Grossman JB, DuBois DL. Using volunteer mentors to improve the academic outcomes of underserved students: The role of relationships. Journal of Community Psychology. 2015;43(4):408–429.

13 Herrera 2007 - Herrera C, Grossman JB, Kauh TJ, et al. Making a difference in schools: The Big Brothers Big Sisters school-based mentoring impact study. Philadelphia: Public/Private Ventures; 2007.

14 Chan 2013 - Chan CS, Rhodes JE, Howard WJ, et al. Pathways of influence in school-based mentoring: The mediating role of parent and teacher relationships. Journal of School Psychology. 2013;51(1):129–42.

15 Grossman 2012 - Grossman JB, Chan CS, Schwartz SEO, Rhodes JE. The test of time in school-based mentoring: The role of relationship duration and re-matching on academic outcomes. American Journal of Community Psychology. 2012;49(1-2):43–54.

16 Schwartz 2012 - Schwartz SEO, Rhodes JE, Herrera C. The influence of meeting time on academic outcomes in school-based mentoring. Children and Youth Services Review. 2012;34(12):2319–2326.

17 Pryce 2013 - Pryce JM, Keller TE. Interpersonal tone within school-based youth mentoring. Youth & Society. 2013;45(1):98–116.

18 BBBS-Annual report 2019 - Big Brothers Big Sisters (BBBS). 2018 Big Brothers Big Sisters of America annual impact report. 2019.