Facebook isn’t just Facebook. The company is massive, and has a whole suite of other apps and businesses it launches (or acquires) from time to time. The latest is kind of a pared down social network aimed at busy teens on the go — but that comes along with massive, glaring privacy flaws that could leave kids at risk.

As Quartz reports, the new app, Lifestage, launched last week. It’s kind of like a Yik Yak / Snapchat hybrid, and it lets teens connect to their school to share videos, likes, dislikes, and reactions.

There’s no direct messaging, and it’s not really a photo platform, so it neither supplants nor competes with Facebook’s other massive platforms (Facebook, Messenger, Instagram, etc.). It’s just sort of an… online high school.

But it apparently doesn’t actually do any screening or verification of who signs up. “The authors of this post,” the authors write, “are 24 and 29 years old respectively, which some would say is too old to be in high school.” And yet neither one of them had any problem pretending to be 17 and signing up for Lifestage as students at Brooklyn Technical High school and Manhattan Business Academy. Other decidedly non-teenage colleagues of theirs were also able to pretend to be high schoolers and sign up for the app.

That’s because all it needs is your phone number, unlike early Facebook which required you to have a very specific e-mail address (first, one from a certain set of schools; later, any one ending in .edu) in order to register.

And unlike Facebook, which lets users set up various levels of privacy settings and non-public profiles, Lifestage is all-public all the time. Anyone on the network — not just at your high school, but at any high school — can see it. And it encourages users to link their other social profiles, like Instagram and Snapchat, to their Lifestage login.

The app does warn users that public means public, displaying the text, “Everything posted is public. Audience cannot be limited in any way. We can’t promise that anyone in a school actually goes to that school” during the sign-up process, Quartz says. But teens may be likely either to flick through that warning and back away, or not quite processing the full import of it.

When Quartz asked Facebook why on earth it thought this was a good idea, a representative for Facebook said, “We are releasing Lifestage to a limited number of high schools. Lifestage will not provide access to content from other people for users who list an age above 21. We encourage anyone using the app who experiences or witnesses any concerning activity to report it to us through the reporting options built into the app.”

They also added, “We take these reports seriously. Unlike other places on the web, Lifestage is tied to a person’s phone number and only one account is allowed per phone number – this provides an additional level of protection and enforcement.”

Of course, plenty of other social places on the web — including, these days, Facebook — can be tied to a phone number as well. And a number, without any further verification, is just that: a number.

Since there is no mechanism by which to verify a user’s age if that user says, “Uhh, sure, I’m, uh, totally under 21,” and no mechanism to keep content private, any creeper who wants to keep an eye on a certain high school kid, or all the high school kids, very easily can.

Of course, all that depends on actual real human kids actually wanting to use the service to begin with. And whether they do or not, when they still have Snapchat, remains to be seen.

Facebook’s newest app makes it shockingly easy to stalk high schoolers [Quartz]

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