If you are a parent or teacher who spends time with children, you are aware that device use and screen time are issues. Any number of problems are linked to screen time, including eye problems, bad posture, carpal tunnel syndrome, social disconnection, depression and insomnia.

In these times of Cambridge Analytica data-mining, we are also quite aware that privacy violations are a social media occupational hazard. But younger children are protected from all this, right? Not necessarily.

A new study reveals that despite federal protections and explicit company claims, children's privacy is being routinely undermined by popular apps.

In the late 1990s, the Children's Online Privacy Protection Act (COPPA) sought to regulate game, app and websites access to the data of children under 13 years old. More specifically, parental consent is required before collecting personal information.

COPPA was revised and updated in 2013 to include "geolocation markers, IP addresses and a mandate that third-party advertisers comply with these rules as well." Despite this intention, full COPPA compliance remains difficult to achieve.

Today, thousands of Google Play Store's Android apps are said to be in violation of COPPA. Researchers from UC Berkeley's International Computer Science Institute assert conclude that "roughly 57 percent of the 5,855 child-directed apps that we analyzed are potentially violating Coppa."

That's almost 3,000 apps!

Researchers encountered varying degrees of violation, depending on the app:

• 5 percent of apps shared "location or contact information without consent."
• 18 percent shared personal identifiers for ad targeting.
• 40 percent ignored "reasonable security measures" when sharing personal information.
• 40 percent disregarded contractual obligations aimed to protect children's privacy in general.

What's even more confounding is that these apps are included in Google's Designed for Families, a program built around COPPA guidelines.

There's also the issue of the classroom Chromebook, which accounts for half of all mobile devices used in U.S. classrooms. It's cheap, its apps are easy to use, and the cloud makes it easy to access and share information.

Chicago Public Schools alone have spent $33.5 million on 134,000 Chromebooks. Do Chromebook apps also violate parts of COPPA? There is no direct mention of Chromebook classroom apps in this recent study, which focuses on Android apps, but given the sheer number of apps involved, classroom spillover is likely.

Since the Chromebook was so rapidly introduced into U.S. classrooms, it has been suggested that Google's stated adherence to COPPA and school district student privacy protections can't be verified. From scanning Chromebook-based email content for advertising purposes to accessing private info via widely used Google Docs, COPPA violations have been hotly debated.

The study does mention one explicitly educational app, the language-teaching Duolingo, as violating COPPA when it comes to sharing children's persistent identifiers with third-party vendors. This app has been named "iPhone App of the Year," and Google selected it as the "Best of the Best in Google Play."

To make matters worse for Google, last week the Center for Digital Democracy and Campaign for a Commercial-Free Childhood led 20 advocacy groups in requesting the FTC investigate Google subsidiary, YouTube, for massive COPPA violations involving tens of millions of U.S. children.

The problem? While YouTube accounts are officially intended for people over age 13, anyone can sign up for one, and you don't need an account to watch YouTube videos.

Between YouTube access, app violations and classroom usage, Google has its hands full of privacy violation charges these days. The company has declined to comment on recent app allegations.

Jeff Chester, executive director of the Center for Digital Democracy, describes Google's violations as standard company procedure.

"Google has basically looked the other way while it was able to generate revenues off of children's apps," Chester said. "The new, alarming report is further evidence that Google is thumbing its nose at the only federal online privacy law that we have."

Chester ultimately lays this situation at the Federal Trade Commission's doorstep: "For years, the FTC has failed to address how both Google and Facebook routinely undermine consumer privacy."