What should I write in my arrival card as the purpose of arriving on a NON-O visa while being the guardian of a child with an ED visa?

Guardian

"Yes, if you are a guardian traveling with a child to Thailand, you should enter "Guardian" on the new TDAC (digital arrival card) form. The TDAC system typically allows children to be included in their guardian's form.

Here's why and what to expect:

TDAC Requirements:

As a guardian, you'll be responsible for completing the TDAC form, including information about the child you're traveling with.

Guardian Designation:

The TDAC form will likely have a field or option for you to indicate your relationship to the child, which you should identify as "Guardian". "