Even though a good part of learning is visual, the only eye test many children receive is a vision screening at school. According to the CDC, fewer than 15% of preschool children receive an eye exam by a professional. Most schools try to do a good job of evaluating students' vision, but the American Optometric Association found that school vision screenings miss up to 75% of children with vision problems. Ultimately, screening is not intended to replace a thorough, professional eye exam.

School vision screenings are designed to check a child's eyesight, the sharpness of vision or presence of a refractive error. Students' distance vision is usually measured, which may reveal nearsightedness. But a screening usually does not check a child's close-up skills needed for reading, such as tracking, focusing, and binocular vision. Since most school work is performed at arm's length, students who have trouble seeing close-up may .

A vision screening, in most cases, consists of having a child read the smallest line they possibly can on an eye chart. While the school nurses are highly trained professionals, people that conduct vision screenings may not always be adequately trained. Furthermore, a vision screening is usually a measure of central visual acuity and other testing is limited. 

It’s critical that children receive comprehensive eye exams from a doctor of optometry on a regular basis. When vision issues are detected sooner rather than later, patients receive a better prognosis. Children should receive an exam at least once between the ages of 3 and 5, and annually starting before first grade. By following these guidelines, the school vision screening should be an important safety net, calling attention to possible problems as they develop.