It's a tradition at schools in Germany (at least where I live) that after 9th grade, when you don't have a real class anymore, only courses, every class designs a sweater with something on the front and the names on the back and then everyone gets one. As I recently graduated from year 9 I thought it would be nice to show mine :)
We decided to keep it fairly simple, with only the Roman numeral for 9 on one side and the school name on the sleeve. I love it!