It is difficult to know how to respond to this without far more information about what you hope your students will achieve. Are they being prepared for public examinations, learning about the cultures of English-speaking countries, having a good time, or a combination of these and other things?
If it's purely language acquisition, the syllabus of a successful coursebook might be all you need, though with just three levels you might not find that easy. Are your levels in any way at all related to the CEFR levels?
Are you hoping for off-the-shelf curriculums (which may well not be suited to your needs), or are you looking for someone to write curriculums for you? If the latter, I hope you realise that this is work for which most people qualified to do it would expect to be paid for their efforts.