Sending your kid to home school deprives them of so much social interaction, yes there is alot of bad pressures in public school but its your responsabilty to bring up your child in Christ and be a spiritual leader for them. Trying to protect them from the world for 18 years makes no sense. I think christian parents should send their kids to some kind of school outside the home.
That really is a common problem with many home school families. The view is that if they are not ever around the things of the world then they will not go the way of the world. That is a fallacy that backfires alot when those kids turn 18 and have to deal with the real college life or real work life situations that they have not been trained in beforehand.
So, what is the answer to those things? Should we throw a 5 year old to the wolves of public school for 40 hrs a day and allow them to be doctrinated with no chance of parents knowing what is said so they can train their children to take a stand against those things? That really does not seem like a good option. Or if you are not active in the Christian school they are being placed in, then they also can be indoctrinated with bad doctrines as well. The answer is in the mindset of the parents. Protect from the world, or train to stand up against the wrongs, evils etc. That training can come from homeschooling the kids. Here's what that can look like...
Make sure the kids have public school friends. Let them play with kids in the neighborhood, church youth groups, sports programs, 4H, Boy Scouts, etc. That alone will give enough situations, and questions for parents to show how to live by a Christian world view. Remember that it does not take emersing them into the cesspool of public school for 40+ hrs a week, but giving them enough dirt in small amounts to practice how to stay clean when they do have to walk through their own life.
Public school could only be an option for our family, or Christian school for that matter, if I (because the other half is the bread winner) was very active in that school, or had a child that was very open and vocal with communicating the situations etc of their day in order for our influence to be what helps them grow. Who ever the kids are around the most is who's views they will end up with. If the views of the school, or the views of the group they are around the most do not line up with a Christian world view, then either remove them from the situation, or get super involved in the place they are being educated so they can see how to stand up for what they believe in a hostile place.
Homeschooling allows the time for parents with their kids to train them up into a Christian worldview. Not by excluding all other worldviews, but by examining those things in a way that is not presented as truth. Those issues are taken, and then shown by study and real life examples why they are false. After several years of slower drip training like that, then public school may be an option for high school...only don't expect the homeschool kid to last long. Not because they cannot handle it, but because the educators cannot handle them and their independant, non-conformity, and non-political correct way of speech and action.