What is the difference between teasing and bullying?

Yes, that is bullying. I would tell a teacher but if you're worried about them making fun of you more, ask her to keep it anonymous so that the kids may think someone on the bus told her not specifically you. I'm in 10th grade and my EAST project has to do with bullying. Bullying needs to stop as soon as possible and teachers are usually very helpful. And if not, go higher than that and talk to counselors and principals until something gets done because you shouldn't have to put up with that:) Good luck:)