Hey freya,
Umm.. I can definitely see how it can be hard to be a Christian in a public school. Um, I attend a 5A school in a city in the "Bible Belt". Alot of people claim to be Christian, but really aren't, and its hard to let the world know that you are sincere when others aren't.
One very important thing to remember, as a Christian, is that, you must humble yourselves and be a servant. Being a Christian is not about condemning others to hell or about being prejudice against people of other "religions". Being a Christian is about Loving God, and Loving People. Remember what it says in Philipians 2?? Jesus, being in the very likeness of God, humbled himself, and considered himself NOTHING. Wow! Remember, that as a Christian you are a Christ-follower, and that means you are to do exactly what Jesus did and humble yourself, and man that is something I struggle with daily! Remember, Jesus came for the sinners... not for the perfect little Christian who knows all the sunday school answers. And, buddy, if God placed you in a school full of sinners just like you and me, then that's where He wants you and He wants you to be excited about the Gospel and share it with them.
My friend and I were talking this morning about how if we truly believethe gospel, then it'll be something we can't stop talking about... because how can you not be excited about a Man that came to earth, lived a perfect life, healed the sick, rose people from the dead, made blind see, died for you and me and he himself ROSE from the dead... THAT is AMAZING!!! and I had to examine myself after that conversation, and ask myself: Do you truly - i mean whole-heartedly - believe all of this? ... Then why aren't you running your mouth about it? Why aren't you proclaiming it LOUDLY like you should be?
At school, who do you want people to see? A preacher's kid? or Jesus in You?