This may be coming late since some schools are out now, but any out-of-the-ordinary appreciation is very heartwarming to receive because it isn't expected. I grew up in the 60's and no one ever gave gifts, times change.

I teach Sunday School which is very different than "school," the first time I received a gift I was very surprised. Some parents give gifts and others do not but none are expected or anticipated. I think the Starbucks or movie passes are really a nice treat and make me feel extra special.

I still have a drawing one of the kids gave me on my refrigerator right this moment and it is precious because it was spontaneous. Notes of appreciation are the very best and more than enough reward, but if a parent really feels motivated to give it will be appreciated whatever it is.