While writing this article I asked several of my teacher friends what their favorite gifts would be, and a surprising number of them said an oil diffuser. Most of them said they wanted it because it creates a nice environment to work in — one even adds eucalyptus to help kids breathe easier during the sniffles season — but several others also mentioned that teenagers can get a trifle pungent in the warm air of school.
Remember, the gift you give your teacher could also be coming to school smelling clean. And that gift is free!