Look. I am a firm believer in individual rights. If you choose to be an IT expert, to go to college, to have a proper nine to five job, that's your right. It is also your right – if you so choose – to avoid work, to live in squalor and filth, to lie on the floor of your own home, covered in lice. As far as I am concerned, it should be your right to smoke, to consume alcohol – and even (if I made the call) – to use drugs.
But once you've chosen to have a child, rather than use contraceptives or give him away for adoption, you must contend with the fact that it is your obligation – morally and legally – to provide and care for this child. We should accept that there exists a wide variety of lifestyle choices, religions, cultures, that a parent may make. It should be accepted – in my mind – that you may send this child to a Montessori school, or unschool him, or homeschool him. But what you are not allowed to do is to completely ignore your obligation to this child. You are not allowed – for example – to introduce your child to gratuitous amounts of vodka, or glue-sniffing, or whip him with a steel wire. You are to either homeschool the child or to provide for his schooling elsewhere – 'the child doesn't go to school because I can't be prevailed upon to get up in the morning' is not within the legitimate bounds of parenting. Neither is exposing a child to your alcoholic, drug-addled lifestyle. Again – there's a difference between consuming alcohol or drugs and being a complete worthless junky. A very big difference.
Children, being human beings, have rights. Usually – USUALLY! - the best way to enforce these rights, to ensure the children are provided and cared for, is the family unit. But sometimes it's not clear if the child's rights are being secured, and for this reason the law needs to step in.