Hi,

My 1-year Ed visa ( which must be extended every 3 months ) will end in December 2012, and I would like to continue Thai language at different school from January 2013.

Do I need to letters/papers from former school ?

Do I have to apply from outside Thailand ?

Thanks

Do you have multiple entry visa or are you getting extensions every 3 months of a single entry visa entry?

If it is your extension that ends in December then if possible get another 90 day extension and then change to new school for next extension. If not then you would have to leave the country and get a tourist visa until you can get another ED visa from one of the nearby consulates after changing schools.

If a multiple entry visa then you could probably do another border run just before it expires and get another 90 day entry and then get an extension using documents from new school.