The expansion of student opportunity through the flexible spending of Education Scholarship Accounts (ESAs) builds in direct accountability to the parents who choose and hold the power of the purse. Families can select different schools and service providers if they are dissatisfied with how their student is faring. But ESAs can also be designed to broadly measure outcomes, including student academic achievement, while preserving provider autonomy and a healthy assortment of viable options for families. This policy brief argues against solely using states assessments for ESA eligibility and proposes a more balanced approach.