How to become a teacher with existing Bachelors in Mathematics Degree?

I graduated with a Bachelors of Science in Mathematics Degree from a Washington University. Which is the state I currently reside in and would like to teach in. I graduated into the greatest recession our nation has seen since the great depression, but I refuse to let this get me down. Maybe its just that I only felt how bad the economy was after I tried to get a job with only a math degree. Eventually I became what is called an Emergency Substitute for my local high school. This was because the requirement was only a bachelors degree. I'm at the bottom of the rung. They can only call me after all the regular subs are called. The few times I have subed I loved it and would like to go back to school to become a real teacher, or at least be a certified teacher so that I can be a real sub and not an emergency sub.
I never took even one education course though that hasn't stopped me from trying to educate everyone I come into contact with (this is one reason I would like very much to be a teacher.) I was a peer tutor for two years through my college and have been helping family friends with math more recently and also received a 3.83 in college so I know there should be some type of scholarships or grants for me to go back to school. Which school to go to is the question. Which program to pursue another. How to fund it all is a third. I don't think I can get federal funding to go back to undergraduate school because I already have a bachelor's degree, but I haven't done all the research to know. If I can only go to post graduate school what major should I pursue not having had any previous education courses. looking for the cheapest, quickest way to start a career in the teaching field. Asking this question of you is part of my research. I would appreciate any advice that might help point me in the right direction and minimize the amount of wasted time researching.