Hm. I was going to tell you about my nephew who went through an intense anti germ period filled with overzealous hand washing due to a school program that spoke of germs/flue/colds, etc. He was super into it. But . . .he was in second grade. When I saw that your daughter is 11---- that seems less likely, but still a possibility. Have they had any health programs at school? The licking of her sleeve---- well, I'd ignore that. If you see her eating strange thing or licking other things like blinds or shoes (no joke), then that is something to think about. Naturally when we think about the hand washing, we think about OCD. But she would likely have other symptoms. One thing to start looking for is obsessive thought patterns. If you see that or other symptoms, then you can talk to her doctor. (by the way, s ucking on a shirt sleeve is a sign of anxiety in younger children, it is a way of self calming.) I do agree to kind of ignore it. You will notice if she is doing it involuntarily or deliberately that way. good luck
Could she have learned the behavior is anyone else anxious in the family, very often children copy what they hear and see. Also if she sees to are concerned about the behavior could make the issue worse.Try backing off and saying less instead of talking' to her...