Do parents of international school students in Thailand need to pay taxes while living here?

Paying tax is nothing to do with whether you have a kid attending school or not. The starting point is spending 180 days or more inside Thailand which makes you a tax resident, visa is immaterial. Then you have to look at whether you bring assessable income into Thailand in that year and if so you need to file a tax return if it amounts to more than 120k baht. If you pay tax elsewhere and that country has a DTA with Thailand you can claim a credit on the assessable income you bring in for tax you have already paid on that income

Yes, I do, as I’m working here. It is also a requirement for renewing my Non-B visa. I’ll need to show PND 1, PND 91, and a paid tax receipt. Many people ignore the fact that there is an existing system linking visas (and immigration) to the tax system. For me, it is no tax paid, no visa.

Actually the 180 day law has been in place since about 1978, it's only a slight adjustment which has sent expats into a frenzy. I don't know why. Basically it works like this for MOST people. If you've already paid tax in another country it's highly unlikely you'll pay in Thailand. In theory you *might* have to pay the small difference, but the tax office won't be spending thousands of baht chasing a few hundred (Stepping over dollars to pick up dimes). For retirees, most pensions can only be taxed in the country in which they're paid, so are exempt in Thailand. For those with dual tax residency, the country in which they have a permanent home and where most of their economic activities are carried out has sole taxation rights, so Thailand misses out. These are the conditions of Double Tax Agreements which ensure people won't have the sh*t taxed out of them. So to answer your question, most foreigners won't be paying any tax

Most parents who are not working here but choose to come for education are doing it for themselves and not their kids. They are using the guardianship visa for a long term stay.

The law of being tax resident after 180 days is much older than last year. What did change last year was that all monies remitted to Thailand are now assessable if you are tax resident. Previously if they were kept offshore for a tax year they were neither assessable or taxable. Rules changed November 2023 for tax year 2024. I know plenty of people who have paid tax here for years. Every single one was earning money in Thailand though. Employees, business owners or investors.

Most countries have double tax agreements with Thailand, thats why you dont hear people paying I guess, however, you do need to make the report. Im going to do the report just to avoid any trouble that might follow, I dont want to get in a situation where Im asked to do it "now"