Ключевые слова: 4050years, back, blackboard, caucasian, class, classroom, concept, drawing, education, equation, female, formulated, highschoolteacher, instructor, learn, learning, lesson, male, math, mathematics, middle school, oneperson, physics, problem, professor, research, school, scientist, scribble, solution, study, studying, teacher, teaching, theory, university, wall, white, write,