I tried doing that when i was in high school too, but it didnt work out. However, i felt some attraction from her side too. My tips for you are to show her that you sre more mature than the rest of the class. And another is try to get higher marks in her class too.. This will make your relationship with her better as no teacher likes careless students. I dont know what situation you are in but if you can add her on facebook do that too. At some point your going to ask her out for a coffee or something. Being funny helps too(always). When i was in high school, i asked my teacher said she likes a certain restaurant so one time i invited her and i said more people were coming. She arrived there and asked where everyone was but i said i wanted to have dimner with you alone. She started laughing so hard and said that was sweet. I tried to seduce throughout the dinner indirectly but she was too hard i couldnt close. Besides, most teachers are afraid about their repuatition so this can be a hard one. However, there is no reason not to try
good luck