Hang on, guys.
I went to a junior AND senior school. I am CofE. I have to say, that NEITHER school was as in-your-face as some people are making out.
The junior school was the more 'hardcore' of the two, although, I really don't remember it being that bad. Sure, we said prayers in the morning and before going home, and we went to church for most of the church celebrations, but other than that, it was no more 'religious' to the previous junior school that I had attended (non religious, but had 're' based lessons a couple of times a week).
The senior school was MUCH less so. We NEVER had prayers, and were only shipped off to the cathedral for services, I think, twice a year at the most. We were taught about ALL religions and we accepted that everyone has different beliefs. I DO remember trying to get out of going to Cathedral once, giving the excuse of my CofE faith (when in reality I was just trying to skive!), but to no avail. Was told that I don't need to be in a CofE church to practise my beliefs (when the religions aren't that far apart, anyway).
Anyway, if it is right for YOU, DS and YOUR family, then I wish you all the best.
Why don't you try going to local Catholic church on Sunday to see how you get on and how you feel?