Self-disclosure to friends is a potentially useful way for children to pursue a range of desired goals. Here we examined reasoning about the appropriateness of disclosing one's own academic outcomes in a sample of 7-, 9-, 11-, 13-, and 15-year-old Chinese participants (N = 150). The valence of (1) the outcomes to be disclosed and (2) the corresponding outcomes for the potential audience for the disclosure was manipulated factorially, and participants judged whether disclosure was advisable and explained their responses. Disclosure was seen as more appropriate under valence-matching conditions than valence-mismatching conditions. How participants judged each type of disclosure under valence-mismatching conditions varied as a function of participant age: As compared with younger participants, older participants considered disclosure of weak performance to a stronger performer more acceptable and disclosure of strong performance to a weaker performer less acceptable. These findings suggest that older children are more likely than younger children to appreciate that self-disclosing positive performance outcomes can bring social costs, and that self-disclosing negative performance outcomes can bring social benefits.