If you are thinking of teaching in a private (independent) school then not all of what was previously posted might apply. When I looked for a new job in a private setting I contacted a company, Carney Sandoe, who will help you to find a teaching job at most places throughout the U.S.

Hi Leila, Well it depends on what state you live in. Each state will have different requirements for teachers but there are three general facts that are consistent with all the requirements. 1. It was a good idea for you to think of being a substitute. In order to be a substitute all you should have to do is go to your local school board and either attend a meeting or complete paperwork. By being a substitute you develop a relationship with potential employers. 2. You need to take the Praxis exam. If you want to teach chemistry you will need to take the chemistry praxis. Each state has a different score they require for the chemistry. Just google "[your state] chemistry praxis requirement". 3. You need to be certified to teach in that state. Since you have a degree in chemistry and have industry experience as a pharmacist you may not have to do much. Usually you have to do an alternative certification program which means you teach in a classroom for about 6 months. Good Luck Kind Regards, Nathan Turner