Present perfect progressive or Present progressive? I`m confused, pls HELP!

Hello,

I really need your help with English grammar.

I want to become an au pair in England and need to write a letter to my potential hostfamily. I would like to tell them that I`m taking a training course at college to become an educator and have no idea how to write it.

Do I have to write "I´ve been taking a training course to become an educator since 2005." or "I am taking a training course since 2005"? I would go for Present Perfect Progressive, is that correct? You should know that I`m still taking the course.

Thanks for your help and please excuse my English


Janni