How do I tell my atheist family that I am religious?

I was brought up atheist, but after studying Philosophy for two years I became agnostic. Now I can’t help but learn more and more about religion, Judaism in particular and I feel that maybe in the future I would like to convert. I don’t know how to tell my family. They won’t take me seriously and they often mock religion. I understand the objections that they have to orthodox religion but this is something I feel very seriously about. I’m 17. Maybe I’m too young to make a decision like this.. it’s important to me.