AN ATTEMPT WAS MADE TO DEVELOP METHODS FOR OBSERVING AND MEASURING CURIOSITY IN CHILDREN. SPECIFICALLY, THE STUDY WAS DIRECTED TOWARD STIMULUS VARIABLES RELATED TO CURIOSITY AROUSAL, THE RELATIONSHIP OF AGE AND IQ TO INDEXES OF CURIOSITY, AND THE EFFECTS OF CURIOSITY ON LEARNING. SUBJECTS WERE APPROXIMATELY 30 CHILDREN FROM BOTH THE SECOND AND THE SIXTH GRADES OF PUBLIC SCHOOLS. THEY REPRESENTED A RANDOM SELECTION OF AVERAGE, ABOVE-AVERAGE, AND GIFTED IQ RANGES. ALL SUBJECTS WERE USED IN EACH OF THREE EXPERIMENTS. THE FIRST EXPERIMENT WAS DESIGNED TO OBTAIN OBSERVATIONAL DATA ON THE EXPLORATORY BEHAVIOR OF THE SUBJECTS, AND FOR USE IN DEVELOPING CURIOSITY MEASURES. IN THE SECOND EXPERIMENT, RESPONSE FREQUENCIES WERE RELATED TO VARIABLES IN STIMULUS MATERIALS. A THIRD EXPERIMENT WAS DESIGNED TO OBTAIN EVIDENCE ON THE RELATIONSHIP OF INCIDENTAL LEARNING TO THE EXPLORATORY BEHAVIOR OF THE SUBJECTS. RESULTS INDICATED THAT THE VARIOUS MEASURES OF EXPLORATORY BEHAVIOR USED IN THE STUDY WERE SAMPLING QUITE DIFFERENT ASPECTS OF BEHAVIOR, AND IT COULD NOT BE ASSUMED THAT ANY ONE SUCH MEASURE WAS AN ADEQUATE INDEX OF CURIOSITY. (JC)