It seems that the people that homeschool their kids either come from one of two camps: those who are extremely intelligent, and dedicated, and those that are trying to help their kid take the easy way out, so they do the bare minimum, if that to meet the standards.
Or those that public school is not an option for, such as those ranch kids that I spoke of a while ago. Sometimes the parents are not the best qualified for the job, but its the only option if the parents want the kids to be schooled at all.