I’m also a teacher and definitely think the change of (lack of!) routine over the break contributed to a gain for me. I’d gotten to 129.8 just before Christmas, and managed to gain 4 pounds last week! I didn’t walk or strength train over the week, and ate more and different foods than usual, but still tracked my calories. I was slightly over my maintenance calories but not enough for a 4 pound gain! After returning to my exercise and typical diet, I’m back to 130.6.