I support a voluntary moment of silence where students could pray if they wanted to.
That's just stupid. Why waste the time of those who don't want to pray?
Why waste the time of those who don't want to learn algebra? That children might not want to do something is a lame argument to make when discussing whether it is a good idea.
Having a few minutes of enforced solitude intended for personal reflection, during which students might pray if that is their preferred form of reflection strikes me as a good idea. This is despite the fact that most who advocate this do so as way of sneaking God back into the public schools, not because they think quiet contemplation is a good thing.