In my opinion, if you were a student (especially in secondary form), it'll be better to refuse her.I know it will certainly hurt her, however, you should know students should concentrate on their studies.
Second, it depends on how much you love her. Do you two really know about LOVE? It is different from LIKE. We all like many people, but LOVE needs your sacrifices on different things. LOVE one another needs to protect and care about her or him always. Can you do that? LOVE is long-term, remember.
If you really love her and are ready for her love, then why don't you accept it? It is a praise for human to love one another. It is what we are prrecious. The most important thing is you two should be serious of the relationship.
That's all of my opinion, hope it helps you to decide well.
Good luck! :)