that many homeschoolers.
The recipe is simple: ACT prep, ACT prep, ACT prep. Get a great score, and they get in.
They don't have a GPA to keep up for 4 years. As far as measurables, they just need a great ACT score, and with several years to focus on that, reasonably smart kids don't have a problem getting a 30+.
One of the kids I know who followed this path was raised in Iowa by a BYU grad Mom and Dad (Dad also has a Masters and PhD).
Anyway, that's my recent experience.