It popped up on the screen in front of the whole class: "Your business card is crap!"
A third-grade teacher was searching for a particular video clip and up popped the pitchman, selling, well, crap. For the students, it was an amusing moment that made the class titter. For the teacher, not so much.
Every parent faces that George Carlin moment, when mommy and daddy define the 7 words you can never say on television. It's unavoidable, but the Internet brings these words -- and a whole lot more -- to the fore much earlier than schoolyard gossip.
So can we stop it?
There are always filters and special kid-protection software to lock down your computer. Yahoo, for example, has a "SafeSearch" mode to weed out adult sites. But no automated filter is perfect, so parents could find that some disconcerting items still get through. And if Danny is determined, he's going to circumvent any filters you put in place.
The problem is magnified by sites like Facebook and YouTube that rely on free, user-created content. They don't want to offend visitors, but they still want participation, comments and vibrant discussions that engage users (translation: keep you on the site).
Those discussions can easily get out of hand and fill with colorful language. After calling up a Justin Bieber video on YouTube and noticing some rude comments, my 8-year-old said, "How come they let people put swear words on there but not naked people and stuff?"
To deal with such problems, many sites institute age restrictions in addition to filters. Buried in the terms of service that virtually no one reads is a stipulation: Children younger than 13 may not use the service.
YouTube is intended for viewers 13 and older, for example -- although the children's videos and Annoying Orange clips contradict that position. Facebook's terms of service state that anyone younger than 13 should not be on the site as well.
But on the Internet, no one knows you're a dog -- or a little kid -- and Web sites don't have any way to enforce these rules. Consequently, a Consumer Reports survey found that roughly 7.5 million, or about 10 percent, of Facebook's users were under the age of 13. Surprise, surprise.
Some lessons on how sites and parents can deal with the problem can be gleaned from YouTube, which handles massive amounts of user created data. After all, every 60 seconds, 35 hours of video are uploaded to YouTube.
From this torrent of information, YouTube manages to remove most pornographic or violent material pretty quickly -- although the comments section can make a sailor blush. So YouTube also has a "safe" search mode that excises obscene words and blocks videos that might offend.
Some clips require a registered account holder who claims to be 18 or older. Even those adult clips eschew nudity, however, and usually range from Benny Hill-style humor to important but disturbing news reports about events such as protests in the Middle East.
The main bulwark against a flood of inappropriate videos and verbiage at YouTube is you, the viewer.
Like many other sites, users can flag any clip they find offensive. The flagged clips are then scanned, partly by programs that use algorithms looking for items like lots of flesh tones and by programs that suss out users who insist on flagging Justin Bieber videos as offensive. Ultimately, though, the flagged clips go to humans who are members of YouTube's policy enforcement team. If the clip violates established community guidelines, then out it goes.
Likewise, YouTube (and many other sites, including FoxNews.com) let users flag specific comments as inappropriate. The human element is unavoidable. Not all violence should be banned: Important disasters, wars, and revolutions should be reported. And not every image of a naked person should be censored, especially if it's a Picasso or Modigliani.
Ultimately, even if you have as much money and technology as YouTube, you can't simply throw a bunch of programmers at a problem and expect it to be solved. It won't be.
Only we can solve it by watching what our kids do online and where they go. Because, as we all know, there's a lot of crap out there.
John R. Quain is a personal tech columnist for FoxNews.com. Follow him on Twitter @jqontech or find more tech coverage at J-Q.com.