Can my children exit Thailand on land after overstaying their ED visa and re-enter without issues?

Trust Tod's advice. I had some similar worries last year, but overall whatever he said was what eventually happened.

I think you're confused a bit on the process 😕 and I wouldn't waste a second worrying about your young children on overstay OR just clearing their overstay so you feel better..

𝟭. 𝗪𝗶𝗹𝗹 𝘁𝗵𝗲 𝗜𝗢 𝗮𝗹𝗹𝗼𝘄 𝗺𝘆 𝗸𝗶𝗱𝘀 𝘁𝗼 𝗲𝘅𝗶𝘁 𝘃𝗶𝗮 𝗹𝗮𝗻𝗱 𝘁𝗵𝗶𝘀 𝘆𝗲𝗮𝗿? 𝗧𝗵𝗲𝘆 𝗮𝗹𝗿𝗲𝗮𝗱𝘆 𝗱𝗶𝗱 𝘁𝗵𝗲𝗶𝗿 𝘃𝗶𝘀𝗮 𝗿𝘂𝗻 𝘁𝘄𝗶𝗰𝗲 𝗹𝗮𝘀𝘁 𝘆𝗲𝗮𝗿. 𝗔𝗻𝗱 𝗮𝗰𝗰𝗼𝗿𝗱𝗶𝗻𝗴 𝘁𝗼 𝗺𝘆 𝗿𝗲𝘀𝗲𝗮𝗿𝗰𝗵, 𝘆𝗼𝘂 𝗰𝗮𝗻 𝗼𝗻𝗹𝘆 𝘁𝗿𝗮𝘃𝗲𝗹 𝘃𝗶𝗮 𝗹𝗮𝗻𝗱 𝘁𝘄𝗶𝗰𝗲 𝗲𝘃𝗲𝗿𝘆 𝗰𝗮𝗹𝗲𝗻𝗱𝗮𝗿 𝘆𝗲𝗮𝗿.

The rule about visa exempt land entries is TWO entries by land in a calendar year <- (that's Jan 1 - Dec 31)

There is no way the children who you say are now on a 6 month overstay have entered the country BY LAND two times this year, and even if they had they'd have no issue getting OUT of thailand by land (you can exit but if you have two entries this calendar year you can't enter free stamp)

𝟮. 𝗪𝗲 𝘄𝗶𝗹𝗹 𝗯𝗲 𝘀𝘁𝗮𝘆𝗶𝗻𝗴 𝗳𝗼𝗿 𝟯𝗱𝗮𝘆𝘀 𝗶𝗻 𝗟𝗮𝗼𝘀. 𝗪𝗶𝗹𝗹 𝘁𝗵𝗲 𝗜𝗢 𝗮𝗹𝗹𝗼𝘄 𝗺𝘆 𝗸𝗶𝗱𝘀 𝘁𝗼 𝗿𝗲-𝗲𝗻𝘁𝗲𝗿 𝘁𝗵𝗮𝗶𝗹𝗮𝗻𝗱 𝗮𝗴𝗮𝗶𝗻 𝘄/𝗼𝘂𝘁 𝗮𝗻𝘆 𝗿𝗲𝗽𝗲𝗿𝗰𝘂𝘀𝘀𝗶𝗼𝗻𝘀?

As I said there's no way the children have had two visa exempt entries by land yet this year (It's only Jan 31st 😛 ) they'll be fine

𝟯. 𝗢𝗽𝘁𝗶𝗼𝗻 𝟮, 𝘄𝗲 𝗳𝗹𝘆 𝗼𝘂𝘁 𝗼𝗳 𝘁𝗵𝗮𝗶𝗹𝗮𝗻𝗱 𝘄𝗵𝗶𝗹𝗲 𝗼𝘂𝗿 𝗲𝗱 𝘃𝗶𝘀𝗮 𝗶𝘀 𝘃𝗮𝗹𝗶𝗱 𝗮𝗻𝗱 𝗰𝗼𝗺𝗲 𝗯𝗮𝗰𝗸 𝗮𝗳𝘁𝗲𝗿 𝟯𝗱𝗮𝘆𝘀, 𝗶 𝗷𝘂𝘀𝘁 𝘄𝗮𝗻𝘁 𝘁𝗼 𝘀𝗲𝘁𝘁𝗹𝗲 𝗺𝘆 𝘁𝗼𝗱𝗱𝗹𝗲𝗿𝘀 𝗼𝘃𝗲𝗿𝘀𝘁𝗮𝘆.

What is the reason you want to settle the overstay? There's no overstay fines for children under 15 and no banning for children under 18, I know foreigners here with foreign children on multi-YEAR overstays and they have no issue when they exit.

𝗪𝗶𝗹𝗹 𝗜𝗢 𝗮𝗹𝗹𝗼𝘄 𝘂𝘀 𝘁𝗼 𝗿𝗲-𝗲𝗻𝘁𝗲𝗿 𝗧𝗛?

US as in you two who are on ED visa extensions (and would need re-entry permits to get back in) questionable, because at many entry points the people at passport control look at foreigners on ED visas as people who should be IN the country IN school, studying, not leaving the country on them. There are too many stories of people not geting back in who left on ED visa/extensions w/re-entry permits even with a letter from their school saying they know they're leaving the country and it's okay.

If you're going to Lao to a thai consulate there to get a new ED visa and you want to take the kids fine, do it, they won't have issues getting out, OR getting back in free entry stamp (IF they have passports from a country that gets free entry to thailand when you enter 😉 )