I like this post by Nicole Starling, in which she writes positively about sending your children to a public school, without rubbishing those who do otherwise.
We sent all four of our children to the local state school, but our second son went on to the Conservatorium high school, which is still a state school, but special for Music.
I like these excerpts, but the whole article is worth your time:
We've decided to send our children to the local public school because:
1. Our kids don't have any special needs that would require otherwise at the moment.
2. Our local state school is a good school and the kids will be taught well there.
3. There are a few other Christian families who also send their children to the school.
4. We want our kids to learn how to be followers of Jesus in the midst of the world, and learn to love their non-Christian neighbours. We want them to desire the salvation of their friends - to pray for them, to talk to them about Jesus. We believe that this is at the heart of what it is to be a disciple of Jesus, and essential to what we need to teach them as parents.
We don't do this naively. A local public school will have its own secularism that is anti-Christian. The teachers usually don't (explicitly, systematically) share their religious views at primary school, but everything they do will still be informed in some way by their own personal beliefs. And on a larger scale, the curriculum and structures of the school will be intentionally (and appropriately!) secular, and frequently (and inappropriately!) informed by the secularism of the majority of the politicians and bureaucrats who oversee them.
There will be all sorts of things that their teachers will say, out loud, about religion, sex, the environment, success, and so on, that are inconsistent with what the Bible says. And in addition, of course, there will be all the things they don't say; the six-hour-long silence, every day, in which they don't say anything about the God who made the world - all the things they think they can teach as if He was irrelevant. All of that is part of the deal, and we know that's the case!
So Dave and I don't just wave goodbye to our kids at the school gate and wish them luck! We pray with them, we talk about how they are to behave when they're there, we debrief in the afternoon when they get home and in the evening, when the stories finally come out. We try to get to know our kids' friends, to invite them round to our home to play, and to get to know their families. We aim to get involved in the life of the school - in the P & C, on the School council, in the classroom helping with reading - one day, maybe even Canteen duty! And we try to be vigilant with what happens at school, so that we don't just shrug our shoulders in resignation when things happen that are inconsistent with (good) policy.
There are still days when I do long to homeschool - but on days like that I try to remind myself that I am a homeschooler - just one who happens to send her kids out on a six-hour excursion to the local primary school for 200 or so days of the year. When they're off at school, we don't stop being responsible for them, and there are some vital things we need to teach them that would be very hard for them to learn without going there. (I don't mean maths and science and so on - I mean how to stand against the crowd, how to respect and obey non-Christian authorities, how to be overtly Christian in a non-Christian environment, and how to give an answer when they're asked about the reason for their hope.)
Our strategy is not to send them out into the minefields as child-soldiers, untrained and unarmed and unprepared. Our strategy is to send them out day by day, for part of the day, for part of the year, so that they will learn to be soldiers, both now and when they're grown up, and to do all we can to train and equip them along the way.