We've all heard that statement from parents and I'm sure it is meant with all sincerity - "I don't want to impose a religion on my children... they can make their own decision when they're older." I'm not trying to sound insensitive here but... it's a crock.
First off, whatever you teach your children, they're going to make their own decisions when they get old enough. That is human nature. It is what we, as parents hope for, that our children will grow into fully functional adults who can look at complex issues and make decisions for themselves. You can't make it happen, and more importantly, you can't stop that from happening. To imply that somehow by raising a child in a religious tradition will keep them from making their own decisions about faith is just silly.
But there is a way a parent can make it more difficult... By not giving a child a perspective, by not providing the child with tools, you can make it much more difficult for them to make informed and intelligent decisions regarding religious life. Let me give some parallel examples. When our children hit age 9, they were required to take up a musical instrument. Alexis chose folk harp and John chose violin. We paid for lessons and made them practice. John got pretty good as a violinist and Alexis still has her harp, but neither really plays any longer. That was their decision... but had they decided otherwise, starting instruments in adulthood is much more difficult than starting as a child. Believe me, I know.
Second, neither of our children were forced to learn a second language as a child. Guess what, both are mono-lingual. I think Alexis would have been very gifted there and has touches of a variety of languages but the pathways of her brain were not formed correctly as a young child to make learning languages easier and she only has a smattering of each. Let me give a positive example. Both of my children grew up in very diverse settings interacting with people of a number of racial groups, economic classes, educational backgrounds, and sexual orientations and identities. Both are able to easily fit into just about any setting and be respectful and empathetic.
And here is a direct example. Some years ago, one of my close friends with two daughters, one the age of my daughter, suddenly passed away. His young family was in a shambles but the church did exactly what a church is supposed to do and offered an amazing amount of support and caring. It happened that the wife had grown up in a family with no faith. Her sister watched as the church rallied around her and as her own faith gave her strength in a time that made no sense to anyone. The sister was literally amazed. I learned about a year later that she had gone home and began a search for a faith that she could embrace. It wasn't easy as she had no idea even where to begin... except she had seen faith in action as a community of grace and love cared for her sister and nieces. How different from her nieces' perspective when they grew up knowing what a real faith community looks like and how it acts.
For an adult to "make their own decision" regarding a religious tradition, it is sooooo much easier when they have a background, a perspective, a language from which to begin. That child very well may reject your religious tradition, but if you really want to enable them to make an informed and meaningful choice when they're older, give them a background in childhood. Let them participate in a tradition and discover the riches there. Give them a language so they know what they truly need and truly don't. Let them see what faith in life really looks like. Give them training so they have someplace to start.