Are you ok with teaching creationism in public schools? Being government run schools, the government decides what gets taught. It cannot be teachers teach whatever they want - they must adhere to the curriculum, which is decided by the government.
They might as well teach that Earth is flat - kids are smart, and truth will make its way into their heads regardless. In this day and age, it is hard for it not to.
Why teach them anything at all if the truth will seep in anyway?
Besides, I bet I can think of a looong list of human beliefs once held dear by many people you'd strongly object to being taught in public schools. It's not a free speech issue, because it's paid for by taxpayers, and kids are forced to attend it.
Teach them reading, writing, and arithmetics. Everything else can be learned independently (which is too easy these days) or in vocational schools (which surely do not care about the origins of the universe).
