Cross-age peer mentoring programs, in which teenagers mentor younger children, have proliferated in recent years, yet there is disagreement about the effectiveness of such programs. This study tested whether teen mentors' attitudes about children interact with their mentees' characteristics to moderate outcomes of cross-age peer mentoring. The sample included 221 high school volunteers, 205 mentees, and 182 control group youth. Latent profile analyses yielded two profiles of students who were labeled "academically connected" or "disconnected." Analyses revealed that the academically disconnected mentees who were paired with mentors holding relatively positive attitudes toward youth were more emotionally engaged in the mentoring relationship (than disconnected mentees with more negative mentors) and, subsequently, reported stronger relationships with their teachers at year's end (than did the similarly disconnected children in the control group). Conversely, there was evidence of iatrogenic effects of matching negative mentors with academically connected mentees. Implications for mentor selection and training are discussed. (Contains 4 tables and 3 figures.)