Really, homeschooling is something that the vast majority of parents CAN do. Parents just don't realize how easy and rewarding it is, or they simply believe their children will benefit more from traditional schooling, and that's fine, too. Bottom line, it should be the parents' decision.
I understand that homeschool proponents are going to cite test scores, etc. etc. However, regardless of how many days the parent has failed to get the child to school, regardless of of how many times the family has moved in a school year for one reason or another (the reasons don't always reflect positively on the parents), regardless of whether or not the child was up all night because mom and dad were taken to jail at three in the morning, whether or not there was any food in the house, whether or not Mom got up to make breakfast for the kids, etc. etc. If those kids are enrolled in your school on test day, their performance is counted against your school. Yes, their are schools that do not make the grade. It's not every one of them, and it's not always entirely the fault of the people who are trying to educate the kids. This is not a knock at homeschooling. In many circumstances, it is a wonderful decision. However, there are parents who have no intention of educating their children who take them out of school because they don't care about their child's education. In those cases, it shouldn't be allowed. Homeschool if you want, but make sure you actually are educating the children.