You Shall Not Pass by TeacherMagic.org

Blocks proxy sites, filter evasion exploits, tab spam, and Google Sites abuse on student Chromebooks. Free forever.

You Shall Not Pass (YSNP) is a free content filter for managed school Chromebooks. It blocks the proxy sites, evasion tools, and unblocked games hubs students use to get around school filtering. It runs alongside your network filter and your Google Workspace settings, not in place of them. WHAT IT BLOCKS Web proxies. YSNP recognizes the web proxy and unblocker tools that circulate in schools, including the newer ones that run inside a service worker and the transport methods they depend on, and it blocks standalone proxy and relay services that have no classroom use. Google Sites and Apps Script games. This is the most common route right now. YSNP looks inside Google Sites embed widgets and Apps Script web apps and shuts down game launchers, including the ones that hide a game in a blob, an about:blank tab, a data URL, or an srcdoc frame, or list games in a grid on the page. It also flags a proxy running as a service worker on a Sites page, and in Strict Sites mode removes it, without reading the page code, so scrambling the code does not hide it. Serverless and static hosting. Games and proxies served from common serverless and static hosting platforms are caught, with checks in place so ordinary sites on those platforms keep working. Games on any site. A light guard on every page shuts down blob, srcdoc, and javascript iframes that carry known game code, and stops pages built from known unblocked games hub templates. Tab spam and page flooding. YSNP stops scripts that open floods of tabs or hammer browser history to crash or overwhelm the filter. Tampering. It watches for the tools students run to try to switch extensions off. FOR ADMINS Managed configuration. Push a policy or a hosted config file through the Google Workspace Admin console. Almost every rule and check has an off switch, so you can turn one off in minutes if it gets in the way, without waiting for a store update. Careful about false positives. A built in allowlist of common education sites protects state testing platforms, student information systems, curriculum tools, and assistive technology, where a wrong block is most costly. Checks require strong signals before they act. Strict Sites mode (optional). Blocks every iframe on Google Sites except a built in list of Google and education services plus the ones you add. This is the strongest setting, for districts willing to keep an allowlist. Light on resources. Most scanning runs only when a page changes, so idle pages cost almost nothing. RECOMMENDED SETUP For the best results, force install YSNP through Workspace so students cannot switch it off, turn off Apps Script for your student org unit, and switch on Strict Sites mode. The setup guide on TeacherMagic.org walks through setup and explains what the extension can and cannot stop. PRIVACY YSNP collects no personal or browsing data and sends nothing to TeacherMagic or anyone else. Page content and web addresses are checked on the device only. The only request it makes is to the config URL you set as an admin. Free forever. Made by TeacherMagic.org.