Ключевые слова: abstract, backdrop, background, billboard, black, blackboard, blank, board, chalk, chalkboard, class, classroom, concept, copy, dark, dirty, draw, drawing, education, empty, frame, front, gray, handwriting, learn, lesson, letter, material, message, old, pattern, rough, rubbed, school, scratch, sign, slate, space, student, surface, teach, teacher, template, text, texture, textured, wall, wallpaper, white, write,