Final answer:
Frequent respiratory infections is the priority finding for the nurse to report to the provider.
Step-by-step explanation:
The priority finding for the nurse to report to the provider in a school-age child with cystic fibrosis would be frequent respiratory infections. Cystic fibrosis is a genetic disease that causes thick and sticky mucus production, leading to frequent lung infections. These infections can cause severe damage to the lungs and respiratory system, and early detection and treatment are crucial to prevent further complications.