To teach, you must have a Bachelor's degree. It can generally be in any subject. Then, you must earn a teaching credential (Single Subject to teach Junior High or High School, Multiple Subject for elementary). This involves either having passed enough classes in the subject you want to teach or passing a standardized test in that subject. You must also pass a general test on reading, writing and math. The teaching credential courses are education related, not specific to a subject. Then you must Student Teach (or in some cases be a teaching intern) at a school at the level you hope to teach at.

For private schools, more often than not you do not even need a teaching credential. Many privates hire people just with Bachelor's (though some do require the credential). For this reason many private schools actually pay LESS than public schools do. So parents are paying for teachers who often has less experience and education. Crazy? Maybe a little.

Usually you would get a Masters a few years after you start - because it will increase your pay. But if you are applying for jobs already with a Masters some schools will be reluctant to hire you because you will cost them more.

If you don't love your subject and the children, you may want to consider other careers. Perhaps teaching inservices for businesses or something else where you get to utilize teaching but not with children? Or become a professor?

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Go make your next choice be your best choice
And if you're looking for a boy with a voice, well, baby I'm single.

Are you in the mood for some dude, or are you in the mood to be subdued?