Any expats worldschool their children do you have a tutor or send them to school in Thailand? And what are the costs?

Looking at our options for the years we plan to be there (coming from the uk).

Our kids will be 10 and 8.

Open to all options, T.I.A

Can anyone clarify the information given to me today at immigration - apparently if I put my son on a Non O visa he is not allowed to be in school in Thailand? They tell me to apply for a Non-ED and actually wrote that down. His school can do all of this for me no problem but is this the best route to take. I am getting conflicting advice - some say Non O and others say ED. He is turning 15y in November and we are busy now with the visas (British passport) Thanks in advance