In this research. the concentration of radon gas has been calculated in the classrooms of schools in Diyala Governorate by using the nuclear track detector (CR-39). which was one of the organic solid-state nuclear detectors (SSNTDs). After calculating the radon gas concentration. https://www.roneverhart.com/Cincinnati-Bengals-Pranzo-Lunch-Bag-Cooler-with-Utensils/