As an atheist I feel this is a tricky question to answer as I tend to get shouted at. However Christianity does make it clear, both in sermons, ceremonies such as baptism and confirmation and in the bible, that parents have a duty to ensure their children are bought up in the Christian faith. At christenings godparents also assume a responsibility to ensure the child grows up in the correct faith. The Christian faith dictates this to the parents, and so as a true Christian, it is only right to expect that the parents do so.
However (and here is where I get shouted at) I feel that taking the child to church at least once a week from birth until the age of twelve, when most children can begin to really appreciate what is going on, would be prejudice the child, if not out rightly brainwash them against other possibilities. Admittedly the Christian church makes no allowance for other possibilities, and so as a true Christian this would make life a lot simpler.
However, and this can be said for all religions not just Christianity, a child is most likely to follow the path they grow up in. Of great relevance in this question would be the “nature or nurture debate”. Do we as humans with the ability for independent thought follow the paths we grow up in, or by way of nature do we naturally follow one path or another? It may be interesting to point out here that while humans are not the only animals capable of independent thought, we are the only ones with religions.
This is the not the time to answer the questions that point rises, it may be worth bearing in mind that without the contact of religion, very few of us would ever believe in it. A counter argument here of course would be that how did they come about in the first place. The only answers I have to that are that today we have science, theories and an understanding of some things, whereas thousands of years ago smallpox ran rampant and wiped out whole cities. Secondly that if all men are of the one true god, why are there so many religions?
Again a question that does not need answering here. Yet despite those additional questions it does provide room for thought that without contact with a religion from birth or for an extended period of time, there would be far fewer worshippers of any faith. But we must also consider, as Christians would say that God has revealed his truth to us and it is our duty to follow it. Alas though humans are far from perfect. This word of God is revealed to us by other people is it not? And has been done so since the times of Moses and Jesus.
Some of our corruption is bound to have spilled over. This aside Christians still believe in their duty. I have above explored fairly thoroughly two beliefs about whether or not it is right to offer these teachings. Now, if I were placed in the circumstance to decide what would be right for a child in this matter, I would have to say that there are two things that must be considered. Is it absolutely necessary for the child to be involved in the religion at all, and if so which denomination.
As far as protestants as concerned, I believe that they should not take their child to church very often, in fact only to the major festivals such as Easter and Christmas. I would however advise the parents to educate the child at home about their religion, and also about the other religions and not believing until the chid is old enough to make his or her mind up. This is the best way to avoid brainwashing the child, but also to make sure the child receives a mainly Christian upbringing as is required by Christianity, and would be fully aware or and able to participate in church life.
To a catholic I would say something very much the same, but possibly to give the child a little extra teaching about mass and the extra things that happen in a church. Personally I think that it would in fact be best to keep the child at home and teach them about all the religions, in equal amounts until they are old enough to chose for themselves whether they wish to have a religion, or even feel that it is necessary to go to church in order to worship god, he is after all omniscient, so what does it matter where and how you pray, as long as you mean it!