How can I promote a blog about my school?

I'm interesting in making one, I'm in eighth grade. I haven't got permission to do this, since they probably won't want to since they already have a website (but it's really boring). I'm really shy in real life but I find Internet a better way to express myself. I haven't told anyone yet about this blog I'm making, and I'd like to know how can I promote my blog without it being discovered, at least in my own classroom since the school doesn't allow flyers or any type of propaganda or advertisement.