No, that's not what I mean 
I mean TOEFL (Test of English as a Foreign Language)
yes, why?
first time in high school, scored 90%, second time as an unergrad, scored well above 90% (don't remember the exact number).
Olha, I admire your idea to work as a professional interpreter. I think if you consider other spheres, not only "international dating" - you may have more chances for a stable and long-term income. Of course, you may need to focus on a specific area in which you will feel most comfortable translating. For example, i can communicate quite fluently in many spheres, both in English and Russian. But when a friend of mine asked me recently to translate his publication in physics... i'll just say that even with a dictionary it was very hard.
Other business ideas for you: become a "freelance journalist" - offer articles with photos about life in the West to magazines/newspapers in Russia. Or translate articles from Western press for them. Or create a profile of "freelance/independent interpreter and translator" on Russian/Ukrainian jobsearch portals.
Next, your question about TOEFL/IELTS: i presume you are thinking to help students prepare for English Proficiency tests. I personally believe that a textbook and a CD are more than enough to study for this test. Last time I was taking TOEFL, they sent me the textbook with CD for free, when I registered for the test. Plus, those textbooks are available in every library.
I do not think that teacher can add anything useful to this process. Become a "bridge between the textbook and student"? If the student can't read very easy textbook, and wants someone to read textbook and rephrase for him, how is he going to do well on the test? Most of people who are eager to learn will tell you the same. So you will probably have to deal in your work with individuals who either know very little and lack self-confidence, or are plain lazy and will expect you to magically implant in their brain the knowledge they can't acquire otherwise. The magic doesn't work that way.