The idea of bringing an apple to the teacher (as a bribe or just an innocent gift) probably originated in New England in the early days of semi-organized schooling, when teachers were paid mainly in foodstuffs and candles and other necessities to supplement their minuscule salaries. Apples were plentiful, so old-timey teachers probably survived on a lot of pie.
found this same explanation on a few sites, so am thinking it was a simple as payment
We are having a group of Japanese teachers come to visit our school. We would like to give them some small gifts and I was thinking about an apple in some form with a note attached explaining the tradition of an apple for the teacher.
Any other ideas - we're giving logo items from school, maybe something signifying our town, what else?