I always tell my kids that I don't expect a gift from them. First off there is over twenty of them and one of me, I can't afford to buy gifts for everyone. I have had parents contact me and ask what they or their children could do for me for Christmas and I always tell them that the one thing I could really use is a volunteer for a couple of hours to help me out with the small things that take up so much time. Putting words on my word wall, or cutting out laminated stuff, helping me with my copies, stuff like that. I have saved every single Christmas card I have ever gotten, I've never ever ever given away any gift a student has given me and I have a collection of 17 World's Best Teacher coffee cups that I absolutely value over and above my fine china.
I have a food and clothing drive going on my class from Sept. 1 until Christmas vacation, I suggest that instead of giving me something, make a donation to the drive in our classroom's name.
Althought Debi is right in that not every family can afford something, in this area it is pretty much expected by the families, not the teachers, that their children will give the teacher a gift. When there are many kids in the family that really runs into a large expense for them if they buy gifts, but most of them here make them. My favorite gift last year? A dozen tamales!!!!!!!!!!!! LOL The kids know I love them and they made them with their mom.
PS: Donations of books for class are always welcome too! I have one family that has had 3 children in my class over the last 5 years and during the school book fair they pick up a bunch of $2 books for the class.