how far can home schooling go in terms of admission to high school, college? Is there outside authority that verifies actual learning abilities/accomplishments?
You’ll still have to take the SAT/ACT, and I imagine there’s a bit more of an interview process than if you went to PS 103 down the street.
Each state has its own standards for recognizing home schools. Currently 24 states have rules about requiring home schooled students to take assessments in order to prove academic progress. Most of those states have exemptions that allow parents to skip the assessments for various reasons. Applying to a college is no different than any other school. The parent or home school association would provide transcripts to the college. For competitive entry colleges other credentials such as standardized testing or recommendation letters would be more important than for other students.
Missouri doesn’t regulate home schooling in any way. However, the state has admission standards for even the lowest level publicly funded college. They include a minimum SAT/ACT score, and transcripts showing studies in science, English, math, social studies and other stuff.
They also accept a G.E.D. as the equivalent of a high school diploma.
A friend of mine took a bunch of SAT Subject Tests before applying to college.
Every college (or college system) is going to have their own requirements and standards.
I only recently learned that it is possible to take AP tests without being enrolled in an AP class. They are usually good for college credit, as are CLEP and DSST tests and a few others. It’s up to each college how much credit, if any, they’re going to give. Most schools offer some credit for such tests, but a lot of them have limits on the number of credits. Thirty credits in total is a fairly common limit, but some schools are more strict and others more lenient. I should think good scores on those tests would impress admissions officers even if credit isn’t necessarily awarded for all of them.
Most colleges have a provision for accepting a student without a high school diploma. The admission requirements often say something like, “high school diploma or equivalent education level”. Sometimes they call it “early admission”. I was admitted to Auburn University at the age of 15, when I had not quite completed two years of high school. They didn’t care because my ACT score was above the 98th percentile. They did not require me to get a GED.
This is correct. Many private colleges do not require a high school diploma or GED as long as you have shown competancy to succeed in college. I had a 15 y.o. and a 16 y.o. on my floor freshmen year in college. The 16 year old only stayed in college for two years before heading to the NSA. Saying his math skills were fantastic would be an understatement. They were both awkward for 2 weeks before fitting right in- which is also my issue with Big Bang Theory- if you are really that smart, you either figure it out and fit in or you don’t care.
Here’s a discussion board focusing on college admissions and a subforum on homeschooling:
https://talk.collegeconfidential.com/home-schooling-college/
And a homeschooling board and their subforum on getting into college
The students leaving PS 238 (https://ps238.nodwick.com/) actually get more of an interview than somebody who was merely homeschooled. 
By chance, I was looking at Kenyon College (Ohio) today. (Very interesting looking undergraduate physics program.)
They take SAT or ACT. Ordinary students can just quote their results in application, and provide proof later. Home School students must submit official SAT/ACT results at the time of application
It looks like they don’t completely trust the self-reporting of all Home-Schooling applicants.
Not necessarily. My niece has a B.S. in math from UC San Diego and is now a grad student at USC. She was home schooled all through elementary and high school and never took the SAT. Here’s how she did it:
When she was 18 she applied to the local community college, majoring in math. The community college didn’t require the SAT, just some placement tests which she passed with flying colors.
After two years she applied to transfer to the University of California. Transfer students need to provide transcripts and letters of recommendation, but not SATs. She got accepted.
This path also exists in Massachusetts, though without the letters of reference.
Some private colleges only require SAT/ACT scores and things like admission essays, list of relevant life experiences etc. Patrick Henry College being one example.
FWIW, the public university where I teach requires home-schooled students to submit a portfolio of completed work if they have no official transcripts (plus, of course, SAT / ACT scores, which are a requirement for everybody). There’s also some language on the admissions page about the university possibly requiring additional screening tests, although I don’t know how often this is enforced in practice.
I think most home-schooled students do, in fact, produce something resembling a transcript; certainly when I have interviewed home-schooled students for Honors College scholarships (the only situation where I’m involved with the admissions process), they list high school GPAs on their application just like everybody else.
Who gives them the grades? Is there some independent third party? Or is it just their mom and dad? If the latter, does the university consider them credible?
I was briefly home-schooled when I lived on Guam because the public school I was in was such a mess. (And yes Guam is part of the US.) The local Department of Education required evidence that I was doing work out of textbooks that fit their criteria. As long as that seemed fine they accepted that I was receiving a regular education. I didn’t get grades.
This was a long time ago, back in 1990, but these web sites seem consistent with how I remember things:
That second link lists why home schooling might be preferable on Guam, “bullying and the lack of supplies and maintenance” specifically. It has been more than 25 years from when I was there until that article was written but it’s sad that things haven’t changed. I remember that in 8th grade I was pressured to join a gang or risk getting jumped regularly; I chose to stay out of gangs and got attacked a lot. (Also being white meant you were a minority and both kids and adults treated you as dirt, that experience sure stuck with me.)
In any case, I’m sure it varies depending on where you live but that how it worked when I was home-schooled.
My team had a young colleague who had been home schooled through high school. She was an alumna of PHC.
GED is the high school equivalency exam. In theory, SAT and ACT are admission exams: GED is an exit exam.
In the past 50 years that I’ve known about: nobody believes Mom and Dad.
What exactly is a “portfolio of completed work”? Is it a bunch of essays the students have written? An inventory of books and workbooks that were used? Or something else?