Ключевые слова: 1216, activity, adult, afroamerican, answering, boy, casual, caucasian, chalkboard, children, class, communication, course, different, diligence, education, effort, elementary, ethnicity, european, exam, explanation, girl, giving, group, happy, indoor, kids, learning, lesson, many, math, mixed, multiethnic, notes, people, portrait, positive, pupil, school, science, sitting, smiling, students, studying, taking, teacher, teenage, together,