Normal vision for a ten-year-old girl is 5.0 or even 5.0 or more, and a visual acuity of 4.9 is slightly below normal but is not usually considered abnormal. Normal visual acuity for a ten-year-old child is 5.0 or 5.0 or more, and a visual acuity of 4.9 is slightly below normal, but it is not usually considered pathologic. Children’s vision loss may be caused by eyestrain due to overuse of the eyes. Children can improve their eye habits and perform periocular massages to relieve discomfort and improve their vision. If children’s vision loss is caused by myopia, children should be more vigilant, pay attention to protect their eyesight to avoid further vision loss, avoid looking at cell phones for a long time, close their eyes more often to rest or look into the distance, etc. to protect their eyesight and develop good eye habits. It is recommended that patients with abnormal vision should seek timely medical attention to assess their condition and follow the doctor’s instructions for treatment.