These can be very helpful. Most homeschool resource catalogs offer one or two of these. There are also several good books available that detail what should be covered through high school. As more and more homeschoolers graduate colleges are developing their own admissions requirements for homeschoolers. Often these incorporate SAT or ACT test scores and transcripts of work completed.
Private institutions are usually much more amenable to homeschoolers.
Many offer homeschool scholarships. State schools often require a GED and some are also requiring SAT subject tests. High school students should find out the requirements for the schools they are thinking of attending. Most universities will accept you, if you already have 12 credits of community college work. Without the Lord, I don't know HOW we'd do it.