hey sally,
i am a speech therapist, and i primarily work in the school system. teachers are human, and we can be like children when we get gifts. however, we are really dedicated to the children. the greatest gift is to see the children thrive, knowing we are making a difference in their lives. many of the parents give gifts at holiday time and at the end of the year. they insist, because they tell me that they want to show how thankful they are. i tell them that a thank you card that has been personalized means the most to me.
you can always make a donation, and still send a nice card to school with your son. if you want to get something a little more personalized, find out about interests the teacher may have. i have to say that a donation in their name is beautiful, and truly keeps within the chrismas spirit.
hope this helps,
suri