Dulwich is a wondeful school.
It is by far better than the other schools available in Phuket, and is on Par with the large schools in Bangkok and the rest of South East Asia.
I am biased as I work there, but I would not send my kids anywhere else (if I had any).
We follow the English curriculum up to the age of 16 where we take IGCSE exams. At post 16 they join the IB course, which is a similar course to A level, and recogniosed in all universities around the world. Ourresults are excellent, and our students have won various awards, and been admitted to Unis all over the world including Oxbridge in the U.K.
Most academic teachers are sourced from UK, US or Aus, and we have a huge Thai staff support system. The range of subjects we offer is huge across all age ranges.
Before people have a go, I know that it is expensive, but no more than the Bangkok international schools, and a great deal cheaper than British private schools. Details of all this are on
www.dulwich.ac.th
As for the visa, I am not quite sure. I am heavily involved in the boarding side of the school and know that the farang boarders do not have to do any visa runs, even if the parents live outside Thailand. this is a question you will have to ask our admin yourself.
Anyway, let me know if I can help with any specific questions about the school.
website