I believe all religin should be removed from schools, including the pledge of alliegence. I, as a child, didn't say the "under G-d" part of the pledge. This nation was formed under the right of freedom of religion. I understand that most people believe in G-d, and I'm one of them, but there are also many unreligious children and children with different beliefs in those schools. If I were one of them, I would feel very uncomfortable in class. I might even feel oppressed or pressured into changing my beliefs.
The message I'm getting from this part of the pledge is that this nation was formed on the belief of monotheism. Though this might be true, the constitution says that religion should be separate from laws education, etc.
I know that, as long as there is religion, people will try to include it in education, despite the constitution. I can't change that, but I can disagree with it.