Yep. My three are in public school in Portland. I was given a form about vaccinations (four pages), and if I vax'd, I'd sign the front and then provide the proof. But instead, I signed the second page stating I opted out due to religious reasons. The school didn't say a word. They CAN'T legally say a word about the religious exemption, they can't ask what religion or anything like that!
The religious exemption is a good one, since they can't say a word about it specifically, and don't need any sort of proof other than your signature on the form.
I believe the form still asks what vax's they've been given, but I marked none. Now, that's not true, mine are given some. But I've read that even if you sign the religious exemption line, but state they've been given some vax's - the school can ask for proof of the vax's. I didn't want to have to provide proof (my own personal issues with them wanting too much information, IMO), so I just marked none, as I said. Now if an outbreak of something occurs, they could ask me to keep my kids home (sigh, insert rolling eye smiley here), but it is what it is and most likely won't happen.