In Connection Church & Home, Dr. Tim Kimmel says that the main issue is not whether a church has one or separate worship settings. After all, if a church has children worship with parents, that is that church's form of "children's ministry."
The key point is not about the form or method of church, but about the heart motivation of why that method is preferred -- both by the church and by any parent.
Dr. Kimmel cautions parents about "outsourcing" the spiritual development of their children. He correctly notes that this is already being done, for decades. On the other hand, though parents should be the primary spiritual influencer in their child's life, there is nothing innately wrong about other adults being spiritual influences in the lives their children.
Christians tend to prefer their own style of ministry, and look down on others that do differently. Moving away from this battleground, Dr. Kimmel outlines basic principles for "how churches and parents can work together in a grace-based partnership to make each other's efforts more impactful."
Does this book give solid principles and good suggestions? Yes. Does it try to give a single, perfect solution for every situation? Thankfully, no. After all, when it comes to the soul's of adults, teens, and children, we know that ministry is often messy and usually complicated. That's where grace comes in.
There were a few things that I didn't care for in this book, but maybe that's because I can be picky about details and about the importance of context.
First, Dr. Kimmel starts out with definitions of family (= "the domestic church") and church (= "a gathering of domestic churches"). However, he never explains how those definitions are derived. I wish he would have made a Biblical case for those definitions.
Second, he also made an attempt to trace a history for how parents began to outsource and subcontract (to the church) their spiritual responsibility. But I think he overstates how dramatic this change has been recently. For example, he says that only relatively recently did parents focus on "the child's outward behavior, sin-management, and spiritual-image-control." I think those issues have been going on a lot longer than a few decades.
Overall, I think this is a good book, and can be useful to parents and church leaders. Just be careful to see it as it is -- a tool that outlines an general framework, not a "bible" for parenting or ministry.
Interested in your own copy? You can order Connection Church & Home from Amazon.
Edit: Read more about this book on Heart Connection, Moralism, and Grace.