`Global Warming` written on a chalkboard

Keywords:

white, drawing, concept, copy, write, symbol, handwriting, dirty, grunge, empty, message, old, scratch, used, learning, erase, wood, conceptual, back, black, detail, slate, study, text, texture, advertise, attention, background, billboard, blackboard, blank, board, border, bulletin, chalk, chalkboard, class, design, education, global, warming, green, idea, information, keyword, learn, presentation, school, sign, writing,