Ключевые слова: advertising, background, blackboard, blank, board, chalk, chalkboard, childhood, class, classroom, college, communication, copy, dirty, drawing, education, empty, erase, exam, frame, green, grunge, information, knowledge, learning, lesson, list, message, note, old, pattern, remember, reminder, school, scratch, space, student, studying, symbol, teacher, teaching, texture, university, used, white, write,