Ключевые слова: atom, backdrop, background, beaker, blackboard, blank, board, book, chalk, chalkboard, chemistry, classroom, college, dark, design, dirty, dna, drawing, education, erase, experiment, formula, frame, graph, green, grunge, illustration, learn, lesson, molecule, monochrome, old, pattern, physics, repeatable, school, seamless, space, stripes, surface, test tube, texture, water, white, write,