And I don't mean a factual error, so much as a mistake, given their goals.
Why on Earth would, in the course of abstinence-only education, would there be such an emphasis put on how condoms and birth control only work N% of the time (let's avoid the necessary but obnoxious conversation about how the percentages are ill-contextualized and frequently misunderstood, and the further even more necessary conversation about how risk management is a critical element of human life and how avoiding all risks is a farcical way to make sure you die having only ever lived a fraction of a life).
My confusion is that, I perceive myself as largely agreeing with a lot of statements I suspect they would also make. I think children are miracles. I do not think the job of the public education system should encourage fewer children. I think people benefit from being in stable, committed relationships before they have kids. And, I think in my own life, that if my ambition, as a youngster, to have been married by my early twenties, had come to pass, I would be happier for it.
So shouldn't the focus be on preparing people to be functional adults as quickly as possible, showing them to make valuable and irreplaceable allies, friends and partners alike, and giving them skills so they're able to sustain themselves? Shouldn't the message be, we think the sequencing of things is important, so we will show you how to rocket through the obligatory stuff? Shouldn't there exist dating and matching systems so people who are pretty clear on what they want can more easily find each other (perhaps this is only necessary because of the format of online dating – it has rapidly dominated the dating market but obscures signals about e.g. whether someone is looking for marriage, which would be a stone cold bonkers thing to put in a Tinder profile)?
I feel both major social groups in America (and many countries abroad) fundamentally disagree with me about whether an unplanned pregnancy would be good news or bad. I guess I just don't see their point of view. It's not like I carefully chose all my responsibilities. Sometimes you just have a responsibility, and children, of all of the responsibilities you could have, are clearly a pretty tremendous opportunity. Compared to e.g. paying taxes, having children is clearly the most rewarding obligation average people will ever have access to.
So we don't have a conservative sex ed program and a liberal sex ed program, we have two programs where people seem to put the marginal value of the life of a human being at some negative number and care only about how to avoid it. One with abstinence and one with birth control and condoms. Congratulations.
But I suspect, if you were to say this to the type of extremist liberals who care enough about sex ed to show up at school board meetings, they'd agree with my characterization (largely – I've heard a shocking number of people claim having children is immoral). But conservatives wouldn't. They've bought into a strategy that doesn't serve their deeper beliefs, and that, I think, is a true error.