The video I linked showed that 37 states are not doing it well (or at all, really, for 22 of them). Relying on "the home" to teach people sex ed, particularly for low-income minority families, perpetuates the cycle of unwanted pregnancies, and thus, more abortions. You can probably guess which states those 22 are, as well.
Another issue they talked about in the video was lack of information about consent, which arguably is just as damaging as not having condoms ready to go. People (and by people I mean boys) aren't taught that you don't get to have sex if someone isn't a ready, willing participant. So not only is there manipulated, unwanted sex (consensual but pressured), but the pregnancies and STDs that result from it.
SEC!! SEC!! SEC!!
I kid, we're no better.