A good number of states have medical, philosophical, and/or religious exemptions available for children whose parents don't want to vaccinate. That is, in these states the school board can't make you do it and they can't fight with you. These kids don't need to be homeschooled (but as a side note, I think it's a great idea
).
Nobody can be forced to give DHP anywhere in the US. Vets and groomers can require it, but that doesn't mean you have to give it. You can swich vets, etc.
I do see that some have stopped giving them altogether though or don't even give puppy vaccines. To each their own, but this can be very dangerous. I think if you've ever seen a pup with parvo or distemper, you'd change your mind...