I am a secondary school student and I think I have proven an open result, how do I get it out?
Well, as I always say, the academia is a circle with its own established convention to follow. In terms of paper publication, you have to learn how to describe things using the terminology and way of expression accepted by the academia. Normally you need several years of regular university education to master these. 

But in your particular case, I think it would be easier if you could find a mentor in the university (e.g. a professor or a research) who really understands and recognize your research result and has your trust. He could teach you what is a logic and sound research and how to speak in the language used in the academic community.

Another solution is just publish your result on your personal blog (I mean a well-known blog system like google+ or wordpress, so that the timestamp of your post will tell the world you're the original holder of the idea) and try to make your result get noticed by the academic people.

If you really want to challenge people's stereotype about academic paper author, you could also try to publish paper yourself. But it is definitely extremely hard.