I'm a retired first grade teacher and I loved getting baked goodies at the holidays. It made my job at home so much easier with less baking.
I still have the ornaments that the children gave me, especially the handmade ones. I can't really think of any child's gift that I didn't like. I remember the look on the children's faces when they brought in a little something special for their teacher. It's priceless!
Avoid coffee cups is my only recommendation. Teachers get dozens of cups!!!