Ключевые слова: abstract, advertising, backdrop, background, billboard, black, blackboard, blank, board, chalk, chalkboard, class, classroom, college, communication, concept, copy, design, display, draw, drawing, education, empty, frame, green, green board, grunge, institute, learn, learning, lesson, message, note, school, school board, scratch, show, space, student, study, studying, teach, teacher, teaching, texture, textured, used, wall, wood, write,