Eeep, how long have you got, jacob??
In a nutshell...Zoltán Kodály was a 20th century composer and educationalist who felt very strongly that 'music should belong to everyone' and who realised that the voice was the instrument we all possess and was therefore the best way to bring music to the most people. 'Music through singing' would maybe be the shortest way to describe the approach.
He gathered together the best educational principles and teaching tools and techniques (many of these were developed by his students).
There is no 'Kodály Method' as such - just his inspirational writings and the above principles, tools and techniques (the most widely-used and known being rhythm names and relative solfa). How the whole thing is put together is very dependent upon the personality and skills of the teacher - there are good and bad Kodály teachers, as in any other subject or area of music.
Discovering it changed my life and bringing musical skills, knowledge and understanding to as many people as possible remains the driving force in my existence.
I wrote an article about it called 'The Kodály Experience' which was published in the May 2003 issue of the AB's 'Libretto' mag - you can find it on this website - it will give you a bit more info and background.
Many thanks for your interest and apologies for going

, singingnurse!