This study uses administrative health insurance records in Taiwan to examine changes in child mental health treatment around four school milestones including: Primary and middle school entry, high stakes testing for high school, and high stakes testing for college entry. Leveraging age cutoffs for school entry in Taiwan, we compare August-born children to children born in September of the same year. The former hit all the milestones one year earlier than the latter, enabling us to identify each milestone's effect. We find that entry into both primary school and middle schools is associated with increases in mental health prescribing, not only for ADHD but also for depression. Middle school entry is also associated with increases in the prescribing of anti-anxiety and antipsychotic medications. Perhaps surprisingly, there is no run-up in the use of psychiatric medications prior to high-stakes tests. But the use of psychiatric medications falls sharply following the tests. These effects are stronger in counties where both parents and children have higher educational aspirations. Hence, the use of psychiatric drugs increases at junctures when educational stresses increase and falls when these stresses are relieved. [Funding for this report was provided by the National Science and Technology Council.]