It depends on why you want to send them to a Christian school and the type of Christian school it is. Our family has sent our children to a Christian school and they now attend public school. If you want your children to have a Christian education with teachers that have the same values, then a Christian school should be great. I would suggest you check to make sure the teachers are actually Christian, attend church regularly, etc. The school we sent our children to ended up hiring teachers that had a different faith than the school they were attending. After that happened, we pulled our kids and put them in public school. There was no difference in who was teaching them at that point.
I will also say that if we could afford a Christian school, I would put them in a different school, but the schools where we live in NJ will cost me about $20K for one year!
They should receive an excellent education in a Christian school. My daughter did kindergarten in the Christian school and when she went to first grade in the public school, the ENTIRE year was a repeat! She still gets all A's and some of that is probably a testament to the great foundation she received for her schooling.