This report summarizes the findings from a national evaluation of mentoring programs funded under the U.S. Department of Education's Student Mentoring Program. The impact evaluation used an experimental design in which students were randomly assigned to a treatment or control group. Thirty-two purposively selected School Mentoring Programs and 2,573 students took part in the evaluation, which estimated the impact of the programs over one school year on a range of student outcomes. The evaluation also describes the characteristics of the program and the mentors, and provides information about program delivery. The Student Mentoring Program is designed to fund grantees to enable them to provide mentoring to at-risk students in grades 4-8. The ultimate goal of the program is to improve student academic and behavioral outcomes through the guidance and encouragement of a volunteer mentor. Seventeen total impacts in the domains of academic achievement/engagement, interpersonal relationships/personal responsibility, and high-risk/delinquent behavior were measured. The main finding of the Impact Study was that there were no statistically significant impacts of the Student Mentoring Program for the sample as a whole on this array of student outcomes. However, there was some scattered evidence that impacts were heterogeneous across types of students. In particular, impacts on girls were statistically significantly different from impacts on boys for two self-reported scales: Scholastic Efficacy and School Bonding, and Pro-social Behaviors. For boys, the impact on Prosocial Behaviors was negative and statistically significant. For girls, the impact on Scholastic Efficacy and School Bonding was positive and statistically significant. The impact on truancy was negative and statistically significant for students below age 12. There were negative associations between program supervision of mentors and site-level impacts on three of the seventeen individual outcome measures: Pro-social Behaviors, grades in math and social studies, and a positive relationship with the outcome of school-reported delinquency. The report also presented results demonstrating that the Student Mentoring Program represented a fairly low level of intensity in terms of service: although grantees, on average, adhered to the general intents of the legislation and program guidance, they were simultaneously constrained by the limits of the school calendar and the population from which to draw mentors. Thirty-five percent of the control group students reported receiving mentoring either from the program or elsewhere in the community; this finding, coupled with the fact that not all treatment group students met with a mentor, reduced the treatment contrast and may have led to some dilution of the impacts on students compared to expectations. Seven appendices are included; (1) Sampling Design and Methodology; (2) Survey Instruments; (3) Construction of Student Outcome Measures; (4) Impact Analysis Results on Original Student Survey Scales and Measures; (5) Sensitivity Tests; (6) Standard Errors and Confidence Intervals of Main Effects; and (7) Site-Level Predictors and Impacts. (Contains 109 footnotes and 122 exhibits.) ["Impact Evaluation of the U.S. Department of Education's Student Mentoring Program. Final Report" was written with the assistance of Christine Dyous, Michelle Klausner, Nancy McGarry, Rachel Luck and William Rhodes.]