When I was in grade 1, during the class Christmas party our teacher thanked each of us for our gifts with a kiss. If she tried that today I don’t know what would land her in more trouble, the kisses or celebrating Christmas.
When I was in 6th grade, Mrs. Welch (a not too-hot 38-42 year old mom) had all of the boys give her a kiss on the cheek (the facial cheek, of course) under the mistletoe at Christmas time. I remember it fondly, if only for the adolescent joy of having kissed a WOMAN!
The male teacher wisely decided not to follow suit with the girls (this was in the later 70s).