
We have been attending a different church recently, but some of our kids were sick last week end so I let one of our teenagers go to the Sunday morning youth meeting at the church where we are still members. This is a good church that on paper at least is theologically sound and they have a strong heart for evangelism. So by most measures this is a very sound, evangelical church.
My son brought back the sermon notes on the left (from the youth class) which talked about the "30 day silence" challenge. Here is their definition of how to improve prayer: "Find a quite place. Pray that God will reveal Himself. Sit quietly. Clear your mind, don't try to think. There is no time limit. Cross your legs in the lotus position". Well, I added the part about crossing your legs, but you get my point. Put it in a Christian context and it is "prayer". Put it in a Hindu context and it is Hindu meditation. The Christian movement that this comes from is apparently called "Contemplative Prayer" or "Centering Prayer".
The core difference here is that in Christianity prayer is thinking or talking information, but in Hinduism it is usually clearing the mind. Also, meditation in the Christian context is thinking through information, whereas in the Hindu context meditation usually is again clearing the mind. Though Hinduism is very broad, sometimes including most every possible practice, Hinduism in its most common form and Christianity still have opposite concepts of how one reaches enlightenment. Hinduism, in its most common form, seeks for us to realize, usually through clearing our minds, that we are one with Brahman and to detach from pain and pleasure in order to be released from samsara. In contrast, Christianity seeks for us to realize, through reason and study, who God is and what he wants from us. And Christianity seeks for us, through self sacrifice, to reduce real hurting for ourselves and others and to enjoy true pleasure as God designed it. So, Christianity and Hinduism are very much opposites. They can only be seemingly merged when Christian terms are instead infused with Hindu meanings. See Christian Answers for the New Age for a more in depth analysis than I can do here.

To see what a pro-contemplative prayer web site says, see Contemplative Outreach. Note that they believe in the "Indwelling Trinity" rather than just the Holy Spirit and they do not seem to mention any concept of repentance. In short, they are promoting Hindu concepts in Christian terms. For a site that shows how contemplative prayer is making inroads into the Christian church, see the Lighthouse Trails Research Project.
If I wanted my kids to learn contemplative prayer, I would take them to the meditation class which meets every Sunday at 11 AM at the local Theosophical society. They could perhaps even go to the Gong Bath and Singing Bowl classes (at the local Catholic Franciscan order) to help them meditate better. Or instead, maybe I will wait for the Evangelical Christian version: the Organ Bath (give it time, someone will come up with a "Christianized" alternative). I'm not casting dispersions on the Theosophical Society. They are acting in keeping with their beliefs (which I do not share). But Christians who, without thinking through the issues, teach children to "clear their mind" during "prayer" are not in keeping with the Christian teachings they say that they are committed to. And Hindus and Buddhists who try to infuse Christian terms with Hindu meanings (in a Christian context) either do not know the difference or they are being disingenuous.
Dr. Ron Carlson - Eastern Philosophy Expert - Video
Rebuttal of Psalm 62 verses Dr. Lutzer used to support contemplative prayer
John MacArthur vs Doug Pagett video debate on Christian Yoga