Most Helpful Girl
Your first step is to gain your confidence before that final class. It's a now or never. There is nothing wrong with the rejections. The less confident you are is probably the higher you don't get what you want. Learn from those rejections. Just try to be confident.
If she is by herself and you are near her just say hi or give her a small smile and she might take notice of you. Either it works out or not I hope you have some form of communication with her.
Sometimes we think No one likes us but you probably don't notice the girl who might like you