Windows 10: Kids user accounts and family settings

I used an existing one that I think I created for a Skype call in 2012 and hadn't used since to do the Inviting. The child accounts are All new with their existing email addresses.

As soon as I go to log in with the child account, it says to log in with an adult account. When I log in with my account, it goes to validate that my account is actually an adult, and asks for 50 cents on a credit card.
I'm on my phone at a concert or I'd like to some screenshots

 

In that case it sounds like it may just being used as a form of verification for the MSA (Microsoft account) if you're not doing so by getting a code via text message, email, or phone call.

Is the 50 cents charge reversed back to the card later?

 

The charge is the only option available for verification. No, the charges are not reversed

perhaps you don't live in the US, and are not required to verify in the same way based on us federal law?

 

I'm in the US. Interesting that it's not reversed.

 

two of the child accounts I was adding were for children under 13. US federal law treats minors under 13 and minors 13 and older differently, so perhaps the child account you added was for a child 13 or older? When it goes to try and charge me the $0.50 for each child, it references those laws.

If that's not it, I'm kind of out of ideas.

I opted to switch the 3 child accounts that I had created to be adult accounts by putting in their birthday wrong, but id them as children in my windows 10 family. That let me set them up with screen and hour restrictions, and also possibly content restrictions (I haven't added the latter yet).

I still had to give them credit card info for each account in order to swap them from child to adult accounts but allegedly they weren't going to charge me like they were for child accounts. Since I have no plan to give my kids the actual login info for those accounts, it's irrelevant what year microsoft thinks they were born.

I'm going to test later with a 4th fake child as an adult account, and then once it's part of my family I'll update the account to make them a child (by updating the birthdate) and see if it tries to charge me at that point.

 

That would be why then. The MSA accounts I used were for an older age.