Ключевые слова: 1, abstract, advertisement, background, blackboard, blank, chalk, chalkboard, child, classroom, closeup, college, color, communication, copy, design, dirty, draw, education, empty, exercise, frame, green, homework, kid, knowledge, learn, lesson, message, note, pattern, pupil, school, september, space, stains, streaks, strokes, study, surface, task, teacher, text, texture, top, university, view, wall, white, writing,