History 888 Study and teaching 590 Politics and government 322 Study and teaching (Higher) 279 Management 274 Sociology 262 Treatment 258 Rhetoric 232 Vocational guidance 199 Business enterprises 189 Youth development 178 Services for 164 English language 163 Marketing 156 Surgery 154 Training of 154 Nutrition 152 Prevention 152 Research 146 Youth 146 Dentistry 131 Brain 127 Diseases 123 Psychological aspects 116 Periodontics 115 Methodology 108 Career development 107 Dentistry, Operative 107 Dental implants 106 Exercise 106 Academic writing 105 Composition (Language arts) 102 Creative writing 100 Law and legislation 97 Microeconomics 97 Personnel management 97 Macroeconomics 96 Nursing 94 Physical fitness 94 Social aspects 94 Economic conditions 92 Social conditions 90 Mathematics 85 Physical education and training 85 Education 83 Physics 81 Children 79 Physiological aspects 79 Dental technology 78 Health aspects 77 Psychotherapy 74 Diagnosis 73 Language arts 73 Health and hygiene 72 Language arts (Secondary) 71 Adolescence 70 Correlation with content subjects 70 Mouth 70 Teenagers 70 Employees 68 Psychology 68 Biology 65 Patients 64 Arduino (Programmable controller) 63 Slavery 61 Technological innovations 61 Computer programming 58 Programming 58 Medical care 57 Science 57 Business communication 55 Aesthetic aspects 54 Data processing 54 Development 54 Entrepreneurship 54 Indians of North America 54 Interpersonal communication 54 Rehabilitation 54 World War, 1939-1945 54 Child development 53 Web-based instruction 53 Career Mobility 52 Creation (Literary, artistic, etc.) 52 Early childhood education 52 Physical Education and Training 51 Occupations 50 Social life and customs 50 Teaching 50 Wounds and injuries 50 Dental Implants 47 Economics 47 Exercise therapy 47 Food 47 Foreign relations 47 Language arts (Middle school) 47 Nutritional Physiological Phenomena 47 Parenting 47 African Americans 46 Civil rights 46 Communication 46