It seems impossible — with all the awareness about child sex abuse in recent years, with all the background checking going on, with all the parents alert now to any sign of weirdness — that children and teens can still be vulnerable to sex abuse when they participate in activities outside the home.

But consider these two stories from Thursday’s newspaper:

“William Smylie, a Washington state contract worker hired to take foster children on outings, asked Jacob Rogers, a level 3 sex offender, to accompany him on those outings. Rogers, 19, was arrested Tuesday for allegedly molesting two of those foster boys.

“An Ohio principal was charged with a misdemeanor after paying 14-year-old students $15 each to let him kiss their feet.

Sexual predators will find ways to be near children, no matter how stringent the safeguards. So it’s up to parents and other adults to be alert at all times when children join Scouts or church and community groups or any organization that takes children outside the moms’ and dads’ purview.

That said, there is some good news. The high-profile cases of sex abuse allowed people to exit from naiveté about the type of people who abuse children. In the 1970s, when former priest Patrick O’Donnell damaged dozens of young lives, most people still believed that pedophiles looked creepy, and not charismatic like O’Donnell.

So parents handed over their children, often without question, because it wasn’t in our collective consciousness that charming adults would be capable of such gross injustices against our children.

Society has awakened. Organizations that serve children have strict rules now regarding adult-child contact. Staffers and volunteers receive training in appropriate touch and behavior. And parents who raise suspicions are taken seriously.

These safeguards are good, but they came at a price. Displays of natural affection between adults and children are discouraged. Men, especially, can feel awkward about interacting in any way with children they don’t know well. Children as young as 3 and 4 receive instruction in good-touch-bad-touch. It’s a new world.

Safer? That requires constant vigilance. If a principal can kiss the bare feet of his 14-year-old students and a level 3 sex offender can somehow go on outings with foster children, we’re not there yet.