According to 11th Fleet's recent article, currently there are 22 international schools in Taiwan. A “true” international school as defined by Taiwan’s Ministry of Education requires that the student holds a foreign passport. Note this definition is different from a school that offers an international curriculum and does not require a foreign passport. 
There are a variety of International schools in Taiwan, American vs Japanese, religious vs secular, and a European school in between. Check out the full list along with the intro and tuition fees here.
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