Your idea of setting up a Greek-language centre sounds great and may well succeed, but it may take time and require a large initial investment.
There are already teachers in the UAE who have been brought in by the Greek Government to support the Greek community. They provide classes in the afternoons to children and adults. The children usually go to foreign-language schools (mainly English) in the mornings and attend extra Greek classes in the evening.
From my own understanding, there is still a need for more permanent facilities (classes are now run in other schools) and more teaching staff, particularly for adults.
The challenges which may face you in setting up an educational facility include the following:
a) There are specific regulations for setting up educational facilities which are managed by the Ministry of Education. These include, size of rooms, hygiene facilities, accessibility, location, etc. If it is merely a language-learning centre, the rules are more relaxed. The more developed the learning programme the more the rules.
b) If you are registered as a school, then all teaching staff must be accredited by the Ministry, which has its own procedure for doing so.
c) If you intend to offer full primary / secondary schooling, then you need special approval and there are many more specific rules relating to this. Accreditation by the Ministry must be obtained before full-time students can be accepted.
I would recommend that you contact the Ministry of Education for further information, particularly on the minimum facility requirements mandated for the different types of learning centres.
Finally, you may also want to contact the Greek Ministry of Education to see what their needs are to ensure that the students receive valid certification as parents / students will require that all courses offer equivalency to Greek examinations.
Do let me know if you require any further information.
04 November 2008