Ключевые слова: 20s, adult, attention, boys, childhood, children, classmates, classroom, communication, concentrating, copy space, day, discussing, education, elementary school, girls, horizontal, indoors, interested, kids, learning, lesson, listening, looking at each other, man, medium group of people, millennial, multiethnic group, preteens, profession, pupils, school, school kids, schoolboys, schoolchildren, schoolgirls, sitting at desk, sitting on desk, students, studying, teacher, teaching, three quarter length, watching, working, young adult, youth,