Ключевые слова: abstract, advertisement, advertising, announcement, backdrop, billboard, black, blackboard, blank, board, chalk, chalkboard, class, classroom, close, communication, concept, copy, dark, design, dirty, drawing, education, empty, frame, gray, grey, grunge, horizontal, learning, lesson, message, old, pattern, photo, retro, rough, school, slate, smudged, space, surface, teacher, text, texture, textured, vintage, wall, white, write,