They knew that poorer students were less likely to have glasses than wealthier white children, but data were limited on whether simply helping children better focus on the page in front of them might improve their ability to master a skill essential for early learning. They screened several hundred second- and third-graders, gave two pairs of eyeglasses to the ones who needed them (about 60 percent of the group, based on a uniquely liberal prescribing standard) and then they tracked their school performance over the course of the year. The outcomes were notable even with the small sample size—reading proficiency improved significantly compared with the children who did not need eyeglasses. In late 2015, a conversation between Dr. Leana Wen, the new Baltimore City health commissioner, and Johns Hopkins President Ronald Daniels about areas of potential collaboration quickly focused on students’ eyesight. Vision screening by the health department had already identified an unmet need for thousands of children; the research seemed to confirm the value of addressing it in the school setting.