We organized the parents in each classroom and pooled our money (with recommended amounts but allowing for people to give what they could afford), then a small committee bought a big gift from everyone. If there is an aide in the classroom working with just one or a few students, that person is included as well.
There was also a school-wide pool to help with those who work just as hard but for so many classes: music, art, library, computer, physical education, secretary, custodian, etc. Sometimes that was a day with coffee/bagels or lunch brought in for everyone to enjoy in the teachers' lounge.
I can tell you, as a former teacher, that as much as we appreciate the gifts from families, we just can't display or use all of the decor objects that come in ("world's best teacher" figurines, coffee mugs or office supplies, for example). Rather than hurt the feelings of some kids by displaying only some, we wind up displaying none. And after 5-10 years of teaching, there's just a huge amount of stuff ready for the yard sale, you know? Doesn't mean we weren't grateful - just means it's impractical.
So it's really great - for teachers and for parents - when the Room Parent organizes something. If the school-wide parent group organizes something for the support and auxiliary staff, that's even better. We teachers rely on those professionals and their work is no less important than ours. We know that parents can't chip in $20 for every professional who touches their child's life, and none of us expect that. But it's hard on the music teacher who handles 300 kids a week to see those of us with 20 kids heading out the door every day with shopping bags and gift cards.
We also have an educational foundation to which parents can donate in a teacher's name (and for which parents organize fundraising events like trivia bees and spelling bees and auctions - all for adults). Donations can be in any amount, $5 and up. Teachers and paraprofessionals in ANY area can apply for mini grants to fund particular projects in their classrooms or subject areas. Even a grant of $200 to bring in a musical group or to buy some equipment means that teachers don't have to take even more money out of their own pockets to buy supplies or provide an enrichment project not covered in the budget. I know this isn't something you're going to set up between now and December 25th, but it's something for all parents to look at as a way to assist all teachers.
One other thing: not all teachers celebrate Christmas, so it's nice if the gift, wrapping and message card are not specifically Christian. It's a good time of year to be INCLUSIVE and not otherwise.