1. Thai Elite Visa - 5 years for 600,000 baht each - apply before September 15 because prices expected to go up.
2. LTR visa Wealthy Global Citizen - hold USD $ 1,000,000 in assets and invest USD$ 500,000 in Thai bonds, Foreign direct investment, or Thai property. I believe if you are married only one of you has to get this visa. Spouse and children can be added on.
3. One parent can get a visa based on the child being in school, I think.
4. Apply to qualified education program and get ED visa. Since ED visas have been abused, the Elite Visa program may never accept you. You must go to classes.