Short answer
Sheepdog Filter forces SafeSearch on Google, Bing and DuckDuckGo, and YouTube Restricted Mode, for every child by default. Because it's enforced at the network level, it can't be switched off in the browser, and search engines that can't do SafeSearch are blocked.
The problem with the SafeSearch setting
Google's SafeSearch setting lives in the browser or the Google account. A child can switch it off, use a private window, or use a different search engine. Then image search becomes the easiest way to find explicit content.
How Sheepdog Filter locks it
When a protected device looks up Google, Bing or DuckDuckGo, Sheepdog Filter points it at that search engine's own SafeSearch-only servers. The search engine then forces SafeSearch on, whatever the browser setting says. It works in every browser, private windows and the Google app.
Search engines that don't offer a forced SafeSearch are blocked, so there's no back door.
YouTube Restricted Mode
The same trick works for YouTube: Sheepdog Filter points it at Google's Restricted Mode servers, hiding mature videos and comments in the app and on the website. It's on for kids by default, as a separate switch, so you can turn it off for a teen and keep SafeSearch.
Turning it on or off
In your child's Blocking tab, you'll find SafeSearch and YouTube Restricted Mode switches. Both start on.
Sheepdog Filter
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