Thanks for the input. For a teaching certificate they are asking me a 2 years course with lots of fieldwork and I really want to get a job in one year. In that case I should do a Master in teaching which is offered mainly on line for one year. But my question is with my little experience in classroom if this Master will be well seen in my Resume.

I am a Chemical Engineering with an MBA and a Master in Technology Management with 20 years of experience in Product Development in the Industry. My mother tongue is Spanish but I also speak English and German.
I have lived in different countries having raised kids in international schools and I am very interested in starting a new career as a Chemistry or Math teacher in High School . I have experience in teaching Organic chemistry in College some time ago and the last three years I ' ve been working as a substitute teacher and private tutor in an International School.
My questions are :
1) do I need a teaching degree to work as a teacher in International Schools ? If yes do a Master in Teaching or Education will be Ok ? Or a teaching certificate ?
2) with my background , would it be easy for me to find a job as a teacher in International Schools ?
thank you ver much for your input !