Bolstering trust and reducing discipline incidents at a diverse middle school: How self-affirmation affects behavioral conduct during the transition to adolescence.

A three-year field experiment at an ethnically diverse middle school (N = 163) tested the hypothesis that periodic self-affirmation exercises delivered by classroom teachers bolsters students' school trust and improves their behavioral conduct. Students were randomly assigned to either a self-affirmation condition, where they wrote a series of in-class essays about personally important values, or a control condition, where they wrote essays about personally unimportant values. There were no behavioral effects of affirmation at the end of 6th grade, after students had completed four writing exercises. However, after four additional exercises in 7th grade, affirmed students had a significantly lower rate of discipline incidents than students in the control condition. The effect continued to grow and did not differ across ethnic groups, such that during 8th grade students in the affirmation condition on average received discipline at a 69% lower rate than students in the control condition. Analyses of student climate surveys revealed that affirmation was associated with higher school trust over time, a tendency that held across ethnic groups and partially mediated the affirmation effect on discipline. Repeated self-affirmation can bolster students' school trust and reduce the incidence of discipline in middle school, findings with both theoretical and practical implications.