I loved this poster that I made for outside of my door nearer the Winter time! Beginner students learning their early scales, such as D-Major, will enjoy seeing a bulletin board that includes images of hot chocolate, snowflakes and a chimney with "smoke" coming out, and being encouraged to "Warm Up with a D-Major Scale!" Teaching students that before we play, we must "warm up!" - and a scale is a great way to do that!
I hope this image inspires you!