1. Using ordinary clinical thermometers resting oral temperatures were taken in 4,463 schoolgirls between the ages of 6 and 20 years. 2. From 2,500 readings in clinically healthy and apyrexial girls charts were made to show temperature variations. 3. It was demonstrated that in the age group 6-10 the mean temperature was 99.5 F. That in the age group 10-14 the mean temperature was 99.3 F and in the age group 14-20 the mean temperature was 99.1 F. 4. For all age groups the majority fell within the limit of 98.9 – 100 F. 5. It is not uncommon to encounter a temperature of over 100º and up to 100.8º of no pathological significance. 6. Temperature readings are not a reliable guide in the clinical assessment of children unless the above considerations are borne in mind.