I have my M.S. biology from a US University, and not in teaching. What is the best degree/certificate that will allow me teach middle/high international schools overseas.
That is a difficult question to answer becuase without knowing the exact country(ies) you are looking to teach in, I can't really give you the qualification you will need to meet, and therefore I can't specifically direct you towards anyone particular degree/certification.
What I am going to suggest you do is a lot of research about teaching requirements in the countries you are considering. Once you have a better idea about what their requirements are take a look at this like of online teaching degrees and certification programs.
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