I’m guessing they are doing it through the States.
When you homeschool your child, you have several forms that you need to fill out and submit to the State. My thoughts are that the States are sharing that information with the Feds.
Here in Missouri, we have laws that are suppose to prohibit that type of data sharing, but many times those laws go ignored by the bean counters and pencil pushers in our State and local government.
As to how to keep the government out of your business, I’d like know how you can do that, too! LOL
Cheers!
There are NO forms you need to fill out in Missouri. If your child was in public school, you only need to write a withdrawal letter. Educators will tell you that you must register with your district, but you DO NOT have to, and all the homeschool orgs discourage it.